One. Space, a mouse click, or a tap anywhere on the screen all do the same thing, and there is nothing else to learn. A short press flips the blade upward. Holding that same button down makes the blade spin heavy, which is a different action with a different result — so one input covers three verbs, and the third one, bouncing off a staple, is about when you press rather than how long.

A tap flips the blade up and lets it spin normally, which cuts paper but bounces off corrugated card. Holding the button makes the blade spin heavy: it turns gold, it cuts card and shutters, and it falls faster while you hold it. Holding is never free, so the useful skill is holding for exactly as long as the cut needs and releasing to get your height back.

It ends the run — unless you press the button at the moment of contact. The window is roughly a quarter of a second, which is about human tap reaction time, and a successful bounce throws you upward. Staples are the only object in the game that can kill you, and they are also the only object that can gain you height, so late acts often route you through them on purpose.

Speed rises a little each act, but that is tempo rather than difficulty. The gaps between props are defined in seconds rather than in distance, so a faster act does not squeeze your reading time. What actually gets harder is the set of materials on the stage: each act introduces a behaviour that asks a new question, and the stage events interrupt the rules you have just learned.

Reaching the gold line finishes a scene, but the stars are counted from how much of the set you cut on the way. Three stars means you cut everything, which usually costs you height and forces heavy spins you would rather skip. Folded paper is the usual reason a run finishes with two stars rather than three: it never blocks you, so it is easy to sail past without noticing you left it uncut.

Yes, on your device. The act and scene you reached, your coins and your stars are kept locally, so closing the tab and coming back later drops you where you stopped rather than at the beginning. Nothing is uploaded and there is no account to make.