Wow, that level is actually brilliant. It's like you have hundreds of possible routes, a lot of skills, and even though I tried circumventing the key move I just wasn't able to go without it. Finding the key move is not that hard, but turning it into a working solution is still a tricky task, and then the solution uses pretty much every useful skill and almost everything of the level as well as comes down to the last fraction of a second.
I use this opportunity to present one of my old levels again - I think no-one has found the intended solution yet, as it was so easily backroutable.
That challenge is to get every lemming into a different exit - if you find a solution without that though, tell me as well.
One note: at the left, there are two one-pixel gaps. They both can be crossed by a lemming using a miner (only every second pixel works though).
Can I make a suggestion for future challenges:
There should be a rule that you cannot post a challenge for your own level; it must be someone else's. This should make it a bit more interesting.
Well, not exactly more interesting, as new levels are usually more interesting than old ones with a challenge applied to them, but I actually see the point of your suggestion. On the other hand, it's a good platform to present new levels and have additional conditions applied to the solution, as well as refine old ones.
A challenge game concept, as you suggest, could also be done with the original/ONML level, as right now there's just a challenge topic providing a list of challenges.
