you know when you get to the cave that supposely has the tree that taught you all the abilities, you get to 4 doors ( Ice, Fire, Electric, and Earth). I keep getting to a point in the doors that there's a big circle on the ground close to a door and there's a little circle thing with legs that runs around the whole time. what are you suppose to do to get the door to open. if you have to kill the little circle to open the door how do you do it. what is it for that matter.

Use Dragon Time, then get on top of the thing by double jumping, then horn dive on top of it. If you got the timing right, you'll squash it and the door will open, allowing you to pass. (Sometime's there's more than one, though)