Well well well first, the best thing in my opinion was the idea, you nailed the topic. Super original and creative (i only saw one game with this mechanic). The game design is so good. The level design was also very nice : Easy for goofy people who never play 2D games like me but still challenging ! Congrats for that, it's pretty hard to accomplish especially in game jams. You may enjoy the 2nd part of the feedback a bit less so i'll do it fast xD Sounds ! Sound design has a huge importance for me, i wish there were more sounds : landing after jump for example. especially knowing that you have a good taste, all the sounds you picked fit the game perfectly.
Also, the spikes need to be more visible for the player. I didn't find any bug, which is impressive for a jam game !
You can be proud of yourselves you did an amazing job.
ps : Yes i literally copy past the message from discord (: