
Some clash in the first level. Genereally, you want to stick to one style of blocks during a level, but some styles mixed together make a good combination

This mole seems very out of place, as it's not standing on anything and it's in an above ground ice level. This could easily be replaced with another ice block, but if you didn't want the slippery block while still having an ice theme, I would suggest using a pipe.

These ghosts seem out of place. Maybe you could make or find custom graphics that would suit the ice theme?

This pipe could be considered clash, but one thing I noticed was that the pipe is turning away from the faded colours, like the rest of the level.

Spikes should usually be attached to something, and the spikes should just be replaced with normal blocks.

Maybe a checkpoint before the boss fight?

This level wasn't a very good one. Too much clash and cutoff, and the mechanics weren't very good either.

Again, maybe some custom graphics need to be put into effect.

I don't think this drop is very fair, as the player will die if they move at all.
Another thing in this level I didn't like was hidden blocks. Hidden blocks should be used for secret powerups usually. I say usually because earlier in the episode you had a puzzle involving them which was acutally pretty good.

This seaweed should be moved over to the left to avoid cutoff.

Powerup spam is usually frowned upon. A solution would be to have a generator that pumps out the suits at a reasonable pace, maybe 20/30s per suit.