Needs an explainer introduction. The mechanic would be self explanatory in 2D but this 3D presentation is unfamiliar. "Bounce higher using triangles" would suffice.
The bounce itself sounds like it's hurting the character no matter where you land, kinda confusing. There should be clearer audio feedback about what actions are good vs bad. The crunch of a positive land is ambiguous at least at first.
The monster/environment should change in an obvious way when it's time to enter. maybe the music should change or everything changes color. Could the triangles hurt you when the mode flips into 'enter'?
Input feels clunky in a bad way tbh. You're aligning cardinally on a sphere, maybe mouse input would feel more thrilling. Orbital momentum could also be interesting. If mouse input makes it too easy, well that's more opportunity to make the triangles and bullet hell effects tougher.