RefractGleamGrotto

Portrait endless refraction. A prism stands at the centre of a crystal grotto and throws exactly one beam, aimed entirely by dragging a finger. Light curtains close in from every direction and are shattered layer by layer wherever the beam sweeps them, one point each; the dark absorbing regions close in as well, and the beam does nothing to them but get swallowed, which leaves whatever curtain sits behind them unreachable. One beam against a whole circle of incoming traffic is the entire game. The curtains come in faster and thicker the longer a run goes, and the dark regions take up more of it. A Strong Lens lets the beam pass straight through the dark and widens it on the way, and a Reflective Shell throws absorbers off for six seconds. Endless mode with no fixed stage.