Xenon 1 - Hikers Probably a slight backroute, since I do have some skills leftover and it was also completely timing based.

Xenon 2 - Snow Patrol I already said this before in the LP video description, and I believe this still remains true even after seeing all of the Xenon rank, this is my biggest favorite of the entire rank. This was the extremely good kind of challenging that was very satisfying to figure out and solve. Tihs level does a very good job of making you think certain skills "must" go at a particular location. For example, for a long time I kept thinking a digger needed to be used on the first one-way pillar. There were a lot of things that caught me off guard, most notably how to  get around the problem of the climber going out to the right and dying, since we need to save everyone. Once again, incorrect sequencing of skills got me into trouble. The key was realizing that everyone must be collected right above the basher tunnel before bashing to the left. Just a very well done level here, Nessy!

Xenon 3 - Security Weak Spot Easier than the previous level, but still can be a bit difficult. I would say I was kind of a dummy here and kept thinking all the builders needed to be used on the left side of the level.

Xenon 4 - Transcendence Nice builderless level that isn't hard level, but it can still be challenging. I kept thinking that the worker needs to be turned back to the left before dropping down on the right side of the structure at the bottom when all it took was just simply digging and dropping on the left side of it.

Xenon 5 - Ghosts In A Machine This one also wasn't as bad as I thought. Compression for the win on the right side, while turning the other lemmings around to the left by blocking after letting a certain number of them go out to the right with the left entrance.

Xenon 6 - They Complain About Blockades The first level of the rank to surprisingly stump me badly. It was very difficult to know whether you can hold back the crowd or if you need to keep it moving. The closest I came to solving the level was using a builder staircase to keep a basher going, but unfortunately the climber gets lost this way, along with another lemming that drowns in the water, therefore leaving you one short of the requirement. It was also hard to see building at the top of the OWW to turn the climber around. Before this, I kept digging it in such a way so that some pixel of wall to the right was left, therefore forcing me to use either a basher or a builder to turn him around. That definitely took me a while. Also, it took me a while to see how to stop the climber from going to the left and drowning in the water. Took a while to see where to finally start containing the crowd. I must say that's clever with bombing the left side so that no one can go out to the left and then blocking on the right to contain everyone.

Xenon 7 - Super Lemming 2D World Easier than the previous one, but still challenging. I don't think my solution is exactly intended, but it's probably still acceptable. I used a miner to stall one of the lemmings to give the lead enough time to build over the gap to the exit before anyone arrives and falls to the bottomless pit.

Xenon 8 - Life With Mystery This one should be a backroute, since I'm sure I cheesed this level completely. Perhaps building to raise the wall high enough so that everyone is contained between the large wall and the slanted terrain is unintended?

Xenon 9 - NessyTV Presents... Easier than the previous level. This one seems open-ended, so there's probably no one intended solution? Shame that the second billboard needed to be destroyed a bit

Xenon 10 - Time For A Factory Reset Second level of the rank to stump me, surprisingly. I used the extremely timing heavy and fiddly method of blocking at the end of the fencer tunnel so that he turns around while in the middle of his swinging animation in order to break the ceiling for the left crowd to get into it. I feel this is just too cool to break I'm actually surprised that it works, although at the same time the miner also has to be placed very precisely. I watched Icho's solution after I solved this level, and I seriously can't believe I never saw to platform for a bit after the fencer breaks through so that only a digger is needed to merge the left entrance with the right one I feel really dumb for not seeing that.

Xenon 11 - Instant Ninjas Yet another level of the rank that stumped me. My solution seemed somewhat messy and fiddly. Just like the previous one, I watched Icho's solution after I solved this level, and my reaction was, "Wait, I had the solution correct the entire time, I just didn't go far enough with it?" I think it was mostly due to how before I used a miner to delay the second lemming that goes to the bottom with the worker and hence I confused myself, especially since after making the miner tunnel for the crowd there's the tiny gap to the right where the floating steel blocks are and that I needed either another platformer or a blocker to turn them back towards the exit. Not to mention other stuff I kept trying so that I would always be a skill short.

Xenon 12 - Lem Me Go Next Easier than the previous level. Parts of my solution "feel" unintended here?

Xenon 13 - Freeze Frame This seems to be a big backroute. I don't think it's supposed to be this easy! Also, I have a lot of skills leftover.

Xenon 14 - Tether Circus Level Another favorite of mine even if my solution appears to be a slight backroute, since I have a builder and a digger leftover, or if acceptable, seems more efficient than the intended one. Still a challenging one even after having most of the level figured out fairly quickly.

Xenon 15 - When Push Comes To Shove I thought this one was easy. Seems easy for its position late in the rank. Only technicality I forgot about was needing to save the blocker and that's when I realized the digger is needed

Xenon 16 - I Am The Doorway Probably a little easier than the previous one. I think the only hard part here is seeing that a lemming inside the digger pit needs to climb out to the left. Maybe a slight backroute here? I went 1 over the requirement too. Even if it is, the intended solution probably still makes the level easy.

Xenon 17 - The Capital Of Science Definitely harder than the previous two levels. However, this is another favorite of mine. Leaving a builder step past a thin wall so that the climbers will survive to the bottom was clever. Here, it took me a while to see where the miner needs to be used. I kept thinking it was on the thin platform to the left of the huge bridge-like structure instead of at the top. Also using a builder staircase to keep a miner going and bombing a climber to make the wall low enough for everyone to walk into the exit. Very good level that uses these three tricks!

Xenon 18 - Night Surf This one wasn't as hard as the previous one, but this one took me a while only because I kept trying something that just kept failing but I still had the belief that it would work despite me rejecting it as not working for good a few times in the video. I simply kept losing two to the stomper trap, but I still believed that it can be made to work so that only one gets killed. Indeed, the key was the maxing out the RR for the last few lemmings. Even then, this one doesn't seem intended, particularly since I have plenty of skills leftover. Something tells me that the intended solution involves falling through to the bottom right before the stomper trap on the right side?

Xenon 19 - It Bee Like That Sometimes Another really good level. That's really clever with building at the edge in such a way so that the worker turns around after leaving just a single brick (how I managed to save a builder in Xenon 14), as well as a builder step past the thin wall so to break the fall for the climber so he will survive the fall to the bottom. I can still see how this can be challenging, but I didn't think the level was hard.

Xenon 20 - Blue Wedding Nice 2-of-everything level to close off the Xenon rank. Once more, it's nowhere near the hardest level of the rank. There were much harder levels earlier in the rank that I struggled with. This one seems open-ended, so there's probably not an intended solution here.