I enjoyed the theme of the level, with the mushroom biome and the fire below, it felt very ominous. I would love to see some more variety with the backdrops and tiles outside of the playable area. I think it would only take a little bit of work to make this level feel like a lived area.
I definitely enjoyed the challenge of the level. I would consider making some changes for some more optional difficulty. For example, you could move some of the jems to above the spikes you normally run right under, so that the player has to take a different path if they want all the jems. I’d also consider having some jems guarded by non-spikes for variety and optional difficulty. For example, a spike chainer protecting a big jem could add an interesting timing challenge.
Normally I recommend that most levels have a checkpoint, but this one if short enough that it works without it. Still, I could see a situation where you have a checkpoint in the middle and casual players can play it and speedrunners can ignore it. I also like the fact that the jems mean that the fastest time isn’t guaranteed to have the best score, this makes the level more engaging for different styles of players.
Regarding the troll part of the level, the level is short enough for it to be funny instead of frustrating. Still, I would consider adding something on-screen with the level so show it’s at least working, something that turns on or off when it’s switched. I’d also consider putting a sign by it or and arrow pointing at it. When I first tried it, I assumed it was left in by accident.
Overall, a fun level. Some small edits and it could have more reply value and engage different types of players. Finally, I’d love to see some changes with the backdrop and the types of tiles used so there is less repetition in the overall look. Great work!