Single player, by 
Wow, dude, finally you’ve released your own level! Or, better to say, you’ve remade the level that was recently uploaded by Auto1lija. Whatever, let’s review it.
What I liked
- Frankly speaking, I don’t often play multi-tileset levels made with MLLE. It’s a good example of MLLE usage.
- There are a lot of useful hints all over the level and the story about stolen summer helps to feel the atmosphere of RPG.
- Eyecandy and layout are better than in the original level by Auto1lija, but they still can be improved.
What I disliked
- Some sound issues. Looks like each part of the level is supposed to have its own music. “Easter Carrotus” part, however, doesn’t.
- I appreciate an effort you’ve taken to create your custom graphics but it doesn’t look good within the textures made by Nick Stadler. Pixel drawing isn’t that easy. The same discrepancy goes for the corridors made of dull tetris-like blocks. They look awful in Carrotus. If you want to see an example of the great usage of textures from different tilesets check out these links:
https://www.jazz2online.com/downloads/6616/rage-of-aquarius/
https://www.jazz2online.com/downloads/6862/scorpio-key/
This one isn’t so sophisticated and thus is even closer to your intentions. Unedited tiles from two tilesets are used here:
https://www.jazz2online.com/downloads/7456/damn-exit/
- Poisonous clouds are a pretty original idea. Looks like the final area with those clouds is supposed to be the most difficult part of a level, but considering the fact that the clouds hurt you only if you stand on the ground you can easily cross this area by jumping. There are too many gem rings and ammo power-ups and their quantity depreciates their value.
Conclusion
So, you’ve taken elbm.j2l by Auto1lija and tried to make it better. Well, it’s way better now. You’ve fixed BG layers, eyecandy and other issues. But eyecandy still can be improved: you could have used 1st and 2nd layers and the placement of easter eggs doesn’t look natural.
I feel like you tried to make a cool nonclassical thing with an unusual stuff like multiple tilesets in one level. But you forgot the basic features that any good level must have. Level must look pleasant and be fun to play. Maybe more secret places with ammo and power-ups including those that are available for coins and mechanics like wind, falling rocks, water, ect. can improve your level.
Maybe you should make a small, unscripted but tidy level with good eyecandy and weapon/enemy placement? You can use original levels as references.
