Holy crap, addicting and satisfying! I love that you up pitched the energy when you grab em, very nice. My only constructive feedback would be to maybe cheat and make the spike hitbox smaller so that death isn't immediate on what feels like pixel collision, and maybe make the velocity slow down quicker on the walk. Also, i'd consider starting the player with a single rechargable jump (I know the levels would have to be redesigned a bit).
Very well made, I really like the levels you crafted around such a simple mechanic!