Interesting concept! The rolling sound effects are so good!
I feel the camera needs a little work, but you got a very interesting concept. It was cool how every elemental had different physics properties. Jumping as the empty elemental and changing into the air elemental to stay in the air as long as possible was fun! Interactions like this could be expanded to make more complex levels.
I couldn't get the rock elemental action to work. I tried rolling into the walls while holding space, but that didn't do anything. I could, however, use the water elemental to phase through the same walls, but I don't think that is intended.
Nice job! Keep it up!