Cubes were fun to knock around, but for some reason I couldn't enter the portal.
the color changing mechanic was definitely quite creative, although the powerups seemed to make changing colors a waste of your time. maybe its utilised more in the second stage but since I couldnt enter it I have no idea.
In terms of graphics I would recommend making the style of the terrain, slimes, etc to match the asthetic of the cube, I think that would look a lot cooler.
Pretty cool nevertheless.