One year, one month, and one day after its initial release, here's the New-Formats version of Lemmings World Tour at last - the largest pack currently available for NeoLemmix!This remastered version has had all levels adapted that originally featured radiation or slowfreeze.
I still encourage anyone who's interested to try out
the original version for Old Formats, which I will continue to maintain. It includes all levels the way they were originally intended to be!
A huge upside of the New-Formats version is the increased stability. The intense mixing of graphic sets in this pack led to more or less frequent crashes in Old Formats when loading up a level, requiring a simple but inconvenient restart of NeoLemmix 10.13. I have not seen this happen in the New-Formats version yet!

The attached ZIP-Folder at the bottom of this post includes the custom success- and failure jingles, all sprite-set recolourings (including WillLem's Lemminas, which now appear on a couple of levels), as well as
strato_generalmd, my modified version of the general tileset that used to exist in Old Formats. It contains some recolourings of various objects, Colorful Arty's rain and snow animations, as well as pre-placed builder staircases.
If you extract the folder in your core NeoLemmix folder, the styles and levels should automatically end up in their correct respective places.This is the updated version of the graphic set and the pack for NeoLemmix 12.10.0.My Instruments tileset is part of the official styles download now, as well as nin10doadict's cattrap.
The gigalem_treemdbright tileset that appears on the Old-Formats version is currently being automatically disabled by the NeoLemmix player - it will replace any instance of gigalem_treemdbright with gigalem_treemd. Therefore, it doesn't make sense to share the tileset in this thread anymore, because it wouldn't be visible on screen anyway. Consequently, I have replaced all instances of gigalem_treemdbright with gigalem_treemd in the actual levels themselves now. This is just another cosmetic change from Old Formats; the GigaLem Metal Mod levels actually also look slightly different now. I hope we will eventually get the freedom to choose between different shadings of the same tileset in form of a previously-discussed palette-swap feature.
God gave Rock 'n Roll to you*
The music pack can be found here. It consists of my self-recorded rock/metal versions of all the standard Lemmings and Oh No! More Lemmings tunes, except for ONML 04 and the special graphics tracks (Beast, Menacing, and Awesome).
All instruments were played / recorded and all tracks mixed by myself.
For everyone new to this pack: Lemmings World Tour is based on the idea of a Lemmings band touring the world. Every main level is inspired by a song title, with the author line being used to credit the artist who originally performed the song (not necessarily the composer

).
Hence, all the music is played with real instruments, including the success and failure jingles. The levels also depict as many different places in various countries across the globe. Thus, many level titles will refer to a song title and a geographical location at the same time. You will also usually find the flag of the respective country on each of those levels (examples see below).
This pack consists of a whopping 320 levels - 40 for each of the 8 ranks.
These ranks are named: Noisemaker, Amateur, Professional, Diva, Rockstar, Legend, Encore, and GroupieIt also ends with the largest level in existence - one that is too large to even be created with or properly displayed by the New-Formats editor, but was converted from Old-Formats directly, together with the entire pack.
It is strongly advised to switch off the high-quality minimap when playing the very last level (Groupie 40) - game fluency will improve drastically that way.

With that out of the way, let's take a closer look at the ranks!
NOISEMAKERThis rank is all about teaching you essential mechanics of the game and vital, but maybe somewhat obscure skill tricks - rather than the usual X-of-everything levels you might find on the lower ranks in other packs! Pay close attention to the pre-level texts, they can give you essential hints!

Also, beware the occasional troll level. There is a certain infamous, lemming-eating Octopus hiding on this rank, and one of the two levels shown below requires the lemmings to dive in a fountain. Sometimes, this pack will put visual aesthetics over strict, mechanical fairness, but it is the exception rather than the rule.
Level 01, "I clicked a Lem; I liked it!": Destructive skills tank on steel, constructive skills turn around when building into terrain.
Level 02, "I love Rock 'n Roll": one lemming will always slip past a stacker at release rate 1 or higher (with a single hatch)
Level 03, "Into the pits": Basher- and Digger pits to contain lemmings
Level 04, "Going under": It is more efficient to go through larger chunks of terrain in one piece than to waste destructive skills on single smaller obstacles.
Level 05, "Over the rainbow": turning around Miners and Builders with Blockers
Level 06, "Ordinary world":1-of-everything level
Level 07, "Pick me up before you go-go": pickup skills, pre-placed lemmings
Level 08, "Glide and joy": to turn around a lemming on an even steel surface, you can build, then dig, then build into the remnants of the first staircase
Level 09, "Grenade": use release-rate increase to get past triggered traps
Level 10, "Noel nouvelet": 1-of-everything level with NeoLemmix skills
Level 11, "Can't stop this thing we started": build across Digger shafts to force lemmings to fall through facing in one direction only (=Dolly-Dimple trick)
Level 12, "We're not gonna take it": cut off a Builder's staircase behind him to isolate him as a pioneer
Level 13, "Paranoid": horizontal one-way arrows can be dug into, but vertical one-way arrows can't be bashed through
Level 14, "Digital world": exit buttons; digging to create a Climber path
Level 15, "Octopus's garden": introduce the Disarmer, and the fact that Strato likes animal traps!
Level 16, "Jump!": six-pixel jumps
Level 17, "How to save a life": using Stoners as stepping-stones for Builders; getting a second pioneer lemming by trapping the crowd at the foot of a wall and then having one lemming glide over whatever is holding the others back
Level 18, "Stop and stair": three-builder wall, sealing off Basher tunnels with Builders (reverse logic of level 12)
Level 19, "Lemming, I hardly knew ya!": It is possible to fall and climb through Blockers; this allows you to free them with Diggers.
Level 20, "Flight of the bumblebee": the flying-Builder trick (building in mid-air before the Digger falls down)
Level 21, "Rainbow in the dark": cancel one Miner with a Miner into the opposite direction
Level 22, "Locked away": Climbers can be contained by putting constructive skills at the top of straight walls
Level 23, "Shatter me": assigning Floaters and Gliders early or late to influence their speed
Level 24, "Hells bells": making Miners continue with Builders
Level 25, "Bash to you": Bashers can move down slopes
Level 26, "Don't stop me now": cancel one Digger with a Digger looking in the opposite direction --> re-use the Dolly-Dimple trick from Level 11 at the end!
Level 27, "Don't bring me down": You can move Bashers down (see level 25) by digging under them while they are bashing.
Level 28, "Bashing through the snow": cancelling Bashers mid-swipe with Walkers and Builders
Level 29, "Behind blue eyes": isolating a pioneer lemming from behind the crowd instead of from the front
Level 30, "In the army now": using terrain to turn lemmings around before destroying it to let them through in the opposite direction (adaptation of the Dolly-Dimple logic)
Level 31, "The one that go away": using lemmings slipping past Stackers to your advantage
Level 32, "Where them Lems at": using Basher tunnels in creation to turn lemmings around that couldn't turn around anymore once the tunnel is completed
Level 33, "Mein kleiner grüner Kaktus": using Blockers to cancel Diggers that only dig on the edge and don't have terrain right beneath them
Level 34, "Takes two to tango": the double-Builder turnaround (having two Lemmings build right next to each other will cause the one on the front to bump against the staircase of the Builder behind him and turn around)
Level 35, "While my Lemming gently builds": applying the logic from level 32 to use a Builder staircase in-creation to get a lemming across a water pond; once the Builder is finished, this path is closed off completely
Level 36, "Pull me under": putting a Blocker on a staircase to later free him with a Basher
Level 37, "Running up that hill": Bashers can also slope up (see level 25) when facing towards indestructible terrain at a low angle
Level 38, "Rock, Paper, Scissors": Stackers can be used to fill the space between a Stoner's hands and feet, thereby creating a straight wall of 6 pixels in height, which the Lemmings can jump (see level 16) over
Level 39, "Vegas Lights": Stoners can be used to make Swimmers dive
Level 40, "Absolute beginners": Many newbie solutions involve excessive use of Blockers and/or Builders - start looking for approaches without either of them (only for the talisman)!
Vegas Lights
GrenadeAMATEUROn these levels, the skills are grouped thematically (upward-moving, downward-moving, destructive, creative etc.), and the more advanced objects get introduced, such as pre-assigned skills and pre-placed lemmings, splitters, force fields, and teleporters. More landscape-like levels start occuring towards the end of the rank.
Level 01, "It's a long way to the top": all upward-moving skills
Level 02, "Timber (It's going down!)": all downward-moving skills
Level 03, "Walking on sunshine": all horizontally-moving skills
Level 04, "Stairway to Heaven": all diagonally-moving skills
Level 05, "Sugar Baby Lem": all destructive skills
Level 06, "Cliffs of Dover": all constructive skills + Climbers can get over Stackers, but not Stoners
Level 07, "Join me in death": all lethal and "reviving" skills
Level 08, "Who let the dogs out?": Disarmers + pickup skills
Level 09, "Greensleeves": pre-assigned-skill hatches, re-use the Stacker-Stoner trick (Noisemaker 38, only for the talisman)
Level 10, "I like to move it, move it!" splitters
Level 11", Whole lotta Lems": using destructive skills to create Climber paths
Level 12, "Smoke on the water": using water to break falls
Level 13, "Ayo Technology": radiation - using Blockers and Cloners to navigate radiating lemmings
Level 14, "Meet me halfway": Miners and Builders can cross through each other and both continue
Level 15, "Ring, Ring": re-using previous tricks (Stackers create Climber paths, lemmings slip by Stackers, building into terrain or bashing into indestructible terrain to turn lemmings around)
Level 16, "Slide it in": Gliders and Floaters can exit mid-air
Level 17, "Float": Swimmers will always move to the top of water areas, and Gliders will always move to the top of updrafts
Level 18, "Tears in Heaven": using one-way fields to turn around Miners and possibly Builders
Level 19, "Holding out for a hero": pre-assigned skills to pre-placed lemmings
Level 20, "Take me to your Heaven": teleporters
Level 21, "You can't play with broken Lems": anti-splat pads
Level 22, "Firework": using the nuke to bomb towards the exit; re-use turning a lemming around in a Basher tunnel (Noisemaker 32)
Level 23, "Fields of gold": one-use traps
Level 24, "Wonderwall": bouncing Bashers off of Blockers and one-way fields
Level 25, "Radioactive": using radiation as a tool to bypass radiation as a trap
Level 26, "Like ice in the sunshine": slowfreeze
Level 27, "Don't fear the Reaper": compression method to get past traps (re-use logic from Noisemaker 9)
Level 28, "Zombie": zombies
Starting from level 29, the levels are open-ended. The landscape levels also start showing up from here.
Shipping up to Boston
Georgia on my mindPROFESSIONALThe first levels of this rank are going to test what you've learned about the skills so far, requiring several of the previously-introduced tricks, but now without prior announcement!

Also be prepared to navigate some pretty huge cities, as you're playing in more and more important locations around the world.
Moskau, Moskau
Streets of LondonDIVANow you can really start showing off your skills - but don't get too cocky yet!

There are still much harder songs coming...
Weiße Rosen aus Athen
BarcelonaROCKSTARIf you want to play on the big stage, you must master how to control the crowd. Can you hold them back when you have to, and make them move when you want them to?
Streets of Philadelphia
Cold TurkeyLEGENDThe songs on this rank will be remembered for all eternity. In other words: Probably just as long as solving these levels might take you!

Ganglem Style
The Phantom of the OperaENCOREHere you can find levels from my preceding, Old-Formats packs (Paralems, Pit Lems, and Lemmicks) that also were named after song titles. The only one missing is "Turn this club around!" from Lemmicks. Without that one, there were exactly fourty of them, so I thought they would be a good fit here. They were not selected for their quality, though - but indeed mainly for their titles.

So definitely expect these to be easier than the previous ranks, but that might be a welcome relief after the hard stuff!

Also, due to the absence of gimmicks, the Lemmicks levels usually have completely different solutions compared to their first appearance.
We are the Lempions (Pit Lems)
All along the watchtower (Lemmicks)GROUPIEThese levels were created by Colorful Strato and incendoadict: I identified the signature level-design features of most of the active content creators, and then built a level for each of them pretending I were them!

Some people have even had several levels dedicated to them - and no, the "author" line is not being used to spoil that for you. Which level was inspired by whom, that is something you'll have to discover for yourself!

Many of these levels are still named after songs, in which case the author line will mention the performing artist, just like before. Other levels will have non-song names, and therefore no author line either.
Bon appetit!
Take a ByteHave you taken a guess at which user inspired which Groupie level?
Then you can check whether you're correct right here:nin10doadict. His level "Yum Yums" was the first to really introduce me to Raymanni's Food tileset. Plus, I just wanted to make a level with a cat in a kitchen

. Since nin10doadict was the first one to ever LP a pack of mine, the honour of opening the Groupie rank goes to him. Signature element, aside from the cat trap, obviously, is the compression method required at the end.
Flopsy. Hence, it uses all of his graphic sets that were available at the time of the creation of this level in conjunction (Star Zone and Scrap Brain). Aside from being a standard Hard-for-Flopsy level with release rate 99 and Lemmings headed for immediate death, it also contains a glider-stoner combination at the beginning that's pretty whacky. I didn't know back then that glider-stoner stuff was another Hard-for-Flopsy trademark, though

. It just happened, and now I'm glad it's in there, because it just fits perfectly! Also, back when I made this level, I didn't know yet either that Flopsy had made Hard-for-Flopsy levels himself in SEB Lems. So yeah, it's both a level "inspired by Flopsy" as well as "hated by Flopsy".
"Poking fun at how people talk-count: 01" 
Proxima. Look to his post at the beginning of the thread, he basically outlined everything perfectly

. "Waking up the neighbours" was chosen because a) Proxima means "the neighbour" in Latin, and b) because some of the lemming crowds can break into the neighbouring "rooms" / disjoint unions, creating a solution with the single chambers interacting with each other.
Colorful Arty. This level combines pretty much everything I wanted to put into it: A "Boss fight" level, as they appear at the end of each rank in SubLems; a level with a very small number of Lemmings (4); one that uses one of Arty's tilesets (Lego); one that requires two skills to pass through each other (digger and basher); and, finally, if you actually carry out that solution, guess what you get? A cross!

I combined Lego and Sky to create the "cliché image" of a God as a face in the Sky with a big white beard. And since "thou shalt not make for yourself an idol" - in German, people translate this as "you shall not make for yourself an image of God", i.e. don't try to imagine what he looks like - the level in itself also creates a great justification to destroy the landscape with bashers and diggers. These Lemmings aren't attacking God, you know; they're merely destroying an image that shouldn't have existed in the first place.
"Poking fun at how people talk-count: 02" 
Nessy. Okay, I know he's not actually Scottish

. But this level doesn't claim to be a true Scotsman, does it? It's a level pretending to have been made by Nessy, but that isn't the case. It only relies on the Mineshaft tileset, which Nessy made frequent use of in Lemmings Migration. Also, the intended solution uses the basher-blocker turnaround trick, which I had to use twice in Lemmings Migration - even though Nessy told me it isn't actually part of his intended solution in either of those levels. Additional elements are the usage of a builder to prevent a climber from going up to a lethal fall height, and using a miner tunnel in-creation to turn around a second lemming.
The title is a reference to the No true Scotsman-logical fallacy, where you dismiss a valid counter-example against a claim of yours. The original scenario goes like this:
Person A: "No Scotsman puts sugar in his porridge."
Person B: "My uncle Angus is Scottish, and he does put sugar in his porridge."
Person A: "No
true Scotsman puts sugar in his porridge!"
Little detail: The tripped-over mine cart in form of an additional, fake exit tilted sideways and spilling gold pieces on the terrain. That's a neat visual gimmick Nessy used in Lemmings Migration, which sadly won't be possible in New Formats anymore.
Raymanni. Uses his Snow tileset because it looks the most Finnish

. Signature element is the stacker-stoner combination, i.e. using a stacker to enable the crowd to six-pixel-jump over a stoner. I had just heard of this trick for the first time here on the forums right around the time when I picked up on playing Raylems again - and then, Raylems was nice enough to confront me with a snow level where I had to put it into practice right away.
nin10doadict. Pretty much his level building style 1 on 1: LPIV Space tileset + Time limit + having to bash through a wall from two sides because of said time limit + compression method to get past lots and lots of kitties. The level is called (K)itty compression because nin10doadict's own cat is actually called Itty; she had several guest appearances during his LP of my Pit Lems pack. You can notice these whenever nin10doadict shouts "My Itts!" during the videos - hence the pre-level screen

.
Meanwhile, nin10doadict does have his own graphic sets, i.e. Tetris Attack and Lava, but neither of these were available at the time of the creation of this level.
IchoTolot & Proxima. Go figure, right?

This is not a level inspired by his level building style, though - instead, something IchoTolot explicitly mentioned he hates: Disjoint unions. I made the chambers interact with each other via the teleporters, because IchoTolot mentioned this as a possible redeeming quality for disjoint union levels in his eyes. That way, the level became more similar to Proxima's level building style again. Thinking about it, I could have made it more "IchoTolot rage-quits" by adding in hidden traps...

But I didn't think about it back then, and the level is complicated enough in the fair version that it is now.
Duuduu. If you pay close attention, you notice the dot after the level title. This is already the first signature thing, because Duuduu somehow likes to put a period in his level title lines. Also, his level titles tend to be - at least in my personal opinion, no offense

- a bit generic; like, for example, "A normal level" from "A Master Degree in Lemmings", which was the main inspiration for this one (and is actually a pretty awesome and unique level

, merely disguised by what I in this case believe to be an intentionally generic title). I just combined it with a bit of fiddly crowd control on very thin pieces of terrain, because that's something Flopsy noticed as a repeating element during his LP of "A Master Degree in Lemmings". And I used the Marble tileset, because this seems to be the one Duuduu used the most in said pack.
Flopsy. Just in case you hadn't already noticed from the letters "SEB" placed clearly visible in the level. Or by, you know, the fact that I openly state this level is for Flopsy in the pre-level screen. This one was an easy choice, given the song title premise of Lemmings World Tour: Just go with a reasonably successful song by SEB that Flopsy hadn't used in SEB Lems himself.

Then make a big and complex Marble level with some random pickup skills dispersed throughout it, similarly to Flopsy's "Crash Course" or "Tricks of the Trade" level series. Curious little detail: Notice how the "lips" in the level actually form the letters "S", "E", and "B" next to them!
I'm gonna refrain from spoiling who "SEB" is at this point, because that falls into the domain of SEB Lems itself. But obviously, if you just put the level title into YouTube, you're going to find out, anyway.
SQron. The pre-text gives a hint about this by using several words containing the letters "SQ", which are all written as capital letters. And yeah, Motörhead's "Killed by death" actually starts with the line "If you squeeze my lizard, I put my snake on you".

Most of SQron's levels in the "Snack Pack" used Oh no! More Lemmings graphic sets, with Bubble being the most common one. Compression method also was used. I just made the debatable decision of going with the Rock chameleon trap - a) because of "squeeze my lizard", and b) because I wanted to sneak in a hint about "snacky Lemmings", referencing the Snack Pack. Little did I know back then that this was the fastest trap in the entire game!

So you have to get a little creative with your compression methods; simply increasing the release rate won't cut it!

Also, at the end there are several of the chains from the ONML Brick tileset placed right next to each other, creating a very rapid upward staircase. This was also used in a Snack Pack level.
namida. Tree-tileset + bombing climbers + lots of miner-builder interactions. Also the part in the beginning where you have to seal off a hole between two tree trunks with a builder before other lemmings fall in is taken from a Lemmings Plus level, "Just breathe".
"Poking fun at how people talk-count: 03"
Nepster & Colorful Arty. This is my attempt at one of these "fine lines of terrain" mazes as they typically appear in the Marble tileset. The original version of this level took aeons to create, because of all the thin terrain pieces, and the solution was way too dull. So I threw that away in favour of something less microscopic with a more interesting solution. This one strays pretty far from its sources of inspiration, namely things like "Don't cross me" from NepsterLems and "Labyrinth of Lucifer" from SubLems. But I feel it benefitted the overall quality of this particular level.
The title should still tell you how I generally tend to feel about these visually confusing fine-line Marble mazes!

Nessy. The Brick tileset is the other one frequently used in Lemmings Migration. Signature elements are building across a digger shaft to make the lemmings fall through facing only in one direction - like in "Dolly Dimple" from ONML, but Nessy required this e.g. in "Cringe comedy". Also, isolating a lemming from behind a crowd, building across a gap from two sides, and stopping the crowd by bombing next to a steel block are all things I did to solve "A bridge across the chasm" from Lemmings Migration.
Wafflemm. Not only does this level contain the mandatory myriad of buttons and pick-up skills; it also contains Wafflemm's forum avatar in some fashion. Since that iconic structure made from pipes from the Bubble tileset is supposed to simulate a waffle, I thought it would go best with the Food tileset. Wafflemm himself mentioned in a stream that the only thing the Food tileset was missing was waffles!

The title may be a reference to Lemming Bytes, obviously - which happens to go nicely with the Food tileset here

- but actually, most of this level is inspired by Wafflemm's smaller pack, "WaffLems" (which I don't have, unfortunately; I only watched Flopsy's LP of it). There was one Beach level in particular where Lemmings fall from the hatch right into an animal trap, gliders have to be used to bypass it, and a reverse basher is needed to make a wall climbable.
Finally, Wafflemm has the habit of labeling his pre-skilled lemmings' hatches with two pickup skills on both sides, rather than one pickup skill above it. So this is another little detail you can guess it from - just in case the rest of the level didn't make it glaringly obvious to you yet

.
Colorful Arty & nin10doadict. I wasn't able to solve Arty's level "Sniper range", so I looked up the solution in his own LP of SubLems... and thought: "Hey, this can be done with fencers as well!" So I came up with something in the Medieval graphic set, because fencers obviously go well with dragon traps, flavour-wise

. The fact that you have an infinite amount of fencers though makes this one more akin to the Troll rank levels from nin10doadict's CasuaLemmings.
All for Love is the title song to a Three Musketeers movie, and since you have to unite a lot of Fencers, I thought this was an appropriate choice

.
Colorful Arty. This is pretty much a straight remake of his SubLems level "I am R.T.", which in itself is already a parody of the original Sunsoft level "I am A.T.". So it's basically a parody of a parody

. But it is also a reference to the Retro rank of SubLems, of course, where Arty came up with new solutions to existing original Lemmings levels. It's just that I did the same thing to one of
his levels now! In contrast to the Retro rank though, this level is a lot easier than the one it was inspired by, because you have to go the other way round.
Fun fact: I had to rebuild this level by hand, because Arty cleverly switched off the option to dump the level files in the main menu of SubLems. But with a rather regular terrain shape like this one, that wasn't enough to stop me!

Pieuw. PimoLems used degrees of wind intensity as rank names, and Pieuw is from France, so I needed a somewhat successful French song title refering to the wind in one way or another. The title means "The wind will carry us", and actually, that's quite fitting to the solution of the level, which requires a lemming to start building while another one is bashing through a wall, so that this basher simultaneously cuts off the staircase behind the builder, preventing the crowd from following. This is a pretty unique trick I learned in a Brick level from PimoLems, so I just had to go with that!
Strato Incendus. Or can you imagine anyone else who likes Zombies
and Slowfreeze?

Yeah, this one was shameless self-aggrandising. It didn't start out as a Zombie- or Slowfreeze level, though: All I wanted to do was enforcing a Basher going down a Fencer tunnel. So I needed some way to re-obstruct that Fencer tunnel with terrain. Having a bunch of uncontrollable lemmings (Zombies) petrify inside that tunnel without the player wanting them to (Slowfreeze) was the best way I could come up with. Also, I wanted to exploit the fact that at a certain height of terrain under water, non-climber swimmers will dive under it while climber-swimmers will climb up.
Pieuw, Colorful Arty, Wafflemm, Raymanni... Food levels aren't really anyone's exclusive signature thing. This is essentially a combination of all Food-relating structures I could find in various packs: The cheese from "Lemburger Cheese / This level stinks" and the cake from "Piece of cake! / Cakewalk" (Arty's SubLems), the lemonade from "Lemming Soda" (Pieuw's PimoLems), the before mentioned waffle and the Pillar-tileset Hamburger from "Lemburger" (Wafflemm's Lemmingbytes), the Food graphic set by Raymanni. I did recreate all the structures myself by hand, though, no copy-pasting from other people's levels... and so, I added in some pieces of my own, like the ice cream, the pizza, and the french fries

. So now I've contributed my share to the pot-luck dinner party!
Zanzindorf. Using his signature Kiwi knight tileset, this one requires two pioneer lemmings, as many of his levels do. Also, digging into a chamber to use it as a climber-turnaround facility is quite neat, plus sending a lemming up somewhere and bomb him as a faller to free the crowd.
Yung Gotenks. Signature elements are the abundance of walkers, platformers, and builders, plus the Hell graphic set, since Yung Gotenks made an entire pack consisting only of Hell levels... and the fact that the level overall is comparatively easy. No offense here!

The way the pioneer lemming is isolated is a little tricky though, I took this from one of the more challenging levels from Yung Gotenks's packs, can't remember which one it was, though, unfortunately.
The title was really fitting, because the song "We are young" actually contains the line "so we set the world on fire", which goes nicely with the Hell tileset!

bulletride. Essentially a combination of the Lemmings Stampede levels "Deep Six" and "A walk in the park", this one requires the crowd to do something while a builder bridge is being built - because once the bridge is completed, it isn't possible to mine in the right spot anymore.
Dodochacalo. DoveLems taught me this neat little trick of using several diggers to make some space, then use that space to build and close off a basher tunnel, making that basher the pioneer lemming. One of the most creative ways of crowd control I've come across so far! Enforcing it was a little difficult, though, I hope the fire traps at the top of the level are enough...
Also, forcing all lemmings of one crowd to become climbers is a thing in DoveLems, plus the idea of sealing a little gap between two walls to make them climbable. Though one of my levels in Lemmings World Tour also requires the same thing, only with a stacker.
IchoTolot. I couldn't go with having only a "hate" level in here for IchoTolot, right?

So first of all, this level obviously uses IchoTolot's City tileset, which I've made great use of for creating all the geographical locations here in Lemmings World Tour. But there's also a neat little trick I learned from IchoTolot, and that is the fact that a digger who is digging so far at the edge of a piece of terrain that there actually isn't any ground beneath his centre can be cancelled by assigning a blocker to him. The only way to make a digger dig so far at the edge though is to place a builder or platformer there first, and then start digging while the lemming is halfway on that bridge. Additionally, the way the crowd has to be controlled here is fairly common in Lemmings Reunion, to my mind. Finally, what I did to namida, I can't spare IchoTolot from: Pronouncing "th" like "z" is a thing typical of many Germans when speaking English

.
"Poking fun at how people talk-count: 04"
Clam. Apart from the Beach tileset, a thing that's very common in Clammings is vertical scrolling. Few other content creators use it that frequently. This level isn't very complicated, mainly because I haven't gotten too far on Clammings yet - I've played through most of the 10-of-everything levels, and most of the slightly complex levels are already complex enough to stomp me

. But this one is slightly inspired by "Bucket list", and makes use of several NeoLemmix skills that Clam has used quite often in his pack (platformers and stoners, namely).
Deceit. I couldn't really come up with a better name here: What I wanted to hint at is that Deceit's Lemmings contains a lot of levels relying on destructive skills, oftentimes intentionally not providing any creative skills at all, or only so few of them that you only have enough for the bare necessities, i.e. gaps. Every other obstacle has to be overcome by some creative combination of destructive skills. I was pretty impressed by that, so I hope I was able to recreate it somewhat successfully...!
GigaLem. Freedom planet graphic set + Zombies + Radiation. With Resident GigaLemmings, there is an entire pack dedicated to Zombies, the only one in this fashion I know of, apart from namida's original Doomsday Lemmings, of course. Radiation appeared in the Millas pack, but mostly in the fair form that I have come to use as well, i.e. providing you with enough blockers to stop the radiant lemmings, and only using radiation in the first place in order to limit the area where the bombing can occur. This one is fairly far away from its source of inspiration, though; I really wanted to have this place and song in here, so that there would be a famous song refering to Japan. And the Freedom planet tilesets look Japanese, especially the Dragon one, with these iconic trees.
By the way: This one was the very last level in the pack I finished. And I
hated every second of it. Not because of the execution, though; I just had such a hard time coming up with something creative here!

Also, the terrain had to be adjusted quite a lot to give one of the pioneer lemmings enough time to escape from the zombies... the radiation actually wasn't the issue here, but Zombies are moving objects as well, after all. But now, everything works fine, and the player shouldn't face any execution trouble with this level.

Geoffster. Signature visual element is the steel boat at the bottom, with the side scuttles. Signature mechanic is the necessity to use a turned-around builder to gain 1 pixel in height and get over a wall. The second part of the level was inspired by "Planks", as well as its rerun.
Mobius / Call me Bronco. Originally, I wanted to name the level "Call on me, Bronco", referring to the song "Call on me" made famous by Eric Prydz. But then, I read about mobius's hobby of meditation, and thought, fine, let's make the level refer to East Asian practices instead

. An alternate contender for the level title was "Occidentali's Karma", a song by Italian singer Francesco Gabbani from last year about how modern Westerners pick up Eastern customs. But it's pretty much only known inside the Eurovision Song Contest crowd. So I went with this much more famous song by Icelandic singer Björk instead.
Signature elements are the double-duty use of a builder initially required to seal off a water pond, with that builder also being required as part of the path for the later solution. Also, the way to isolate the pioneer lemming here is something I've learned exclusively from mobius: Placing a reverse staircase under the hatch, so that all lemmings go to the left, and then using the last lemming from the hatch (who's still facing to the right) to build the second staircase.
Little visual element: Notice the "torches" that you typically find on top of exits, placed as separate objects everywhere in the level. This is a thing Mobius frequently does, which will sadly disappear, too, in case of a New Formats conversion.
GigaLem. The full title of this Russian song is "Ya ochen rad, ved ya, nakonets, vozvraschayus domoy", translating to "I am very glad, as I'm finally returning back home". But you all know it under a different title

. Yes, folks, it is the Trololo song! And it was chosen because GigaLem's first pack, GigaLems, contained a lot of troll elements - not only hidden traps, which is annoying because that pack is only playable in NeoLemmix 1.43, i.e. without clear physics mode - but also exits covered in bricks, which look like normal exits, though. This particular visual trick only works with the Marble tileset. Also, GigaLems contains a lot of levels where you have to get something done before the crowd arrives, meanwhile that crowd goes on an odyssee across a long path of terrain to give you a little more time.
Alberto Fernandes. His pack "Be smart!" contains lots of random flags, as used in the original two-player levels, placed throughout the levels. Also a lot of steel. On top of that, most of his levels require just a tiny bit of ever-so-slight vertical scrolling. So I literally built than in here, too, just for the sake of it.
Deceit. Yeah, Deceit's Lemmings also happens to contain a lot of very innovative Hero levels, i.e. one of every classic skill, like in the original level "It's hero time!" Since this refers to the skill set, I obviously couldn't combine it with Deceit's other trademark of emphasizing destructive skills so much. So he earned himself two levels in the rank!

kieranmillar. The beginning is something I came up with myself, that happened to turn out more challenging than expected in a pleasantly surprising way. The actual signature trick comes at the end: Here you need to free a blocker by bombing another lemming right next to him, so that a third lemming turns around and falls into the bomber pit, from which he can then start bashing to go underneath a bunch of fire traps. You can't do this from the other side, lest the crowd would walk up into the fire traps while bashing.
So yeah, you don't want your lemmings to see fire, obviously. But the title also enabled me to put the hint about the level inspiration into the
author line for the first time!

(The level is credited to "Ed Kieran".)
Colorful Arty. I think this makes Arty the user with the most dedicated levels in this rank. Which is kind of deserved, given that his level design overall inspired huge portions of this pack - and that he showed interest in LPing it early on!

This particular level, however... is not necessarily a reason for celebration. I knew about this trick, but I didn't think of it as one of Arty's signature things until I got to the Hellish rank of SubLems, where you have to do this nasty flying builder-stuff twice. I couldn't fit it into any of the other Arty levels, so you earned yourself an additional level here - but I'm most certainly not a fan of this trick!

In the end, to make it a little more Arty-like, I made it more artistic by combining different tilesets again, with clouds from Sky and the moon from the Polar tileset. Also, there's an invisible exit, as they appear several times in SubLems. Just like in SubLems though, it should be pretty obvious where it is - as if the title didn't provide enough of a hint

.
Gronkling. A lot of people seem to expect Lemmings Evolution to be one of the hardest packs ever, possibly topping NepsterLems in that regard. While the first five demo levels didn't stomp me as much as I expected - I was able to solve four out of five of them - every single one of them contained very distinctive signature tricks. Making miners go through with builders is already the most "mainstream" of them; using a miner to free a crowd from a digger shaft so that they only come out facing in one direction, and at the same time turning that miner around by hitting steel, that's some nice double-duty usage right there! Also, at the beginning the similarly obscure double-builder turnaround is required (taught in the Noisemaker rank, though

). I went with Gronkling's highly requested Minimal tileset here, which he originally planned to release as a rewards-only thing. Anyways, for all these reasons, it was pretty certain that this level would have to come very late in the Groupie rank. I don't know if it's indeed one of the most difficult ones, but it's certainly very complex, with lots of different stages going on.
bsmith. Hence the name, a famous song including a separate "B". I also could have gone with "Sloop John B"

. A recurring thing I noticed in bsmith's level pack is original Lemmings levels remade in a different tileset - in this case, I went with "Builders will help you here" and made it a Brick level. But obviously, the solution is completely different.
Martin Zurlinden. I noticed that MazuLems contains a lot of snow levels, even though the core premise of this level is taken from a Rock level, where several climbers have to work together to put builders in different spots in the most ergonomically efficient way.
Strato Incendus. For the penultimate level, I played the reverse game and threw together everything that
other people had identified as
my signature level design elements. In fact, nin10doadict's level "Super Mecha Death Gators" from CasuaLemmings is what got the whole idea to the Groupie rank started, where he took my main idea of spiced-up animal traps and developed it further. So now I did the same thing with another animal trap. Also, there's a skeletal alien creature somewhat reminiscent of my "Death Titan", a level which many people seem to have enjoyed in Paralems, even though I myself considered the solution pretty lame. That alien creature breathes fire and has lightning traps in its eyes, so don't try shortcutting here!

Other things I like to do frequently is enforcing swimmer usage to platform over a pont from the opposing side; using stoners as stepping stones for builders under low ceilings; and having a digger pay double-duty to lower a lemming's position and turn around the crowd. This trick proved to be very successful in my Pit Lems "Curse Level", @!#*§$%/!
Finally, I don't know whether backroutes can be considered a signature element of mine, but since I like to test my packs "in the field", probably so?

Well, the name just asked for this stupid pun in the level title...
Nepster. This is my attempt at recreating a Final Frustration-like experience. Signature elements are the 20-of-everything skill set with only classic skills, plus the several crowds you have to unite - plus the fact that from all the skills you have, builders are the one you are most likely going to run out of.

Also, there's a structure which actually consists of Dirt tileset pieces, but which goes very well with the Pillar tileset: The "Diagonal disarray" from the level with that same title from NepsterLems.
I know Nepster doesn't consider Final Frustration one of his best levels, nor even one most representative of his level building style. But it remains a fact that X-of-everything levels are a very common thing in NepsterLems, and I've built other Nepster-style levels in the past, such as "You had it coming" from Pit Lems.
Nepster's levels were outlined to me by IchoTolot during my early days here in the forum as the prime example of fair difficulty, the epitome of the "puzzle" ideal the NeoLemmix community strives for. Hence the title.
This level is simply put the most challenging resource conservation-level I could come up with. I don't know if it's possible to save everyone here, as it is required on Final Frustration - I had to use one blocker facing in the wrong direction, so I couldn't free him anymore later. Hence, you have to save all but one.
But if anyone finds a 100% solution, please inform me! I would make that a Gold Talisman for sure! 
I hope the release of this pack to New Formats can bridge the gap between very easy and very hard packs a little!
It's currently rather difficult to find "intermediate" content. The radiation- and slowfreeze levels from Old Formats could be replicated in New Formats to varying degree - some solutions might be more interesting, some more dull than in Old Formats.
Finally, I have tested each level in the New-Formats version of this pack at least once, but with 320 levels in total, there's always a remaining chance that I've missed something that doesn't work as intended.
So please, report any issues you find, just like you would report any backroutes! 
And with that, all I have to say is:
The stage is yours! 
*The red Stratocaster from the Instruments tileset is a Wikimedia Commons picture created by Johan Förberg.