Keep the stack from reaching the top. That's the whole game.
You start with full power and a few helpers — a preview of what's coming, a hold slot, a landing guide. As power drops, the game speeds up and those helpers switch off on their own. You don't choose what goes. You just keep playing.
No score. You don't pass or fail. Nothing you click decides the result — only how you actually play. There's a short read at the end.