i found a nasty glitch
if you go into the cave then you climb in teh ladder, you enter it. KIll the mushroom, open the chest and jump a few times, you cant. WHen you exit teh cave, you just "jump" into the sky. YOu will stop and cannot go down. It is probably a scripting error. Maybe if you dont add any plateforms it might work. But good game keep it up!