The dungeon looping and seeing secrets hidden in plain site on revisit felt good, left to a constant cycle of "am i stuck" into "aha!" moments. Loved the Mario 2 inspiration as well, a nice mechanic to pull.
My one criticism is the controls, having jump, pluck and unlocking doors being tied to 3 different inputs felt a bit un-intuitive and led to a lot of misinputs. Condensing it down to two buttons (as well as allowing for WASD movement) would be appreciated.
Fun game overall!