The game One-Hit-Ko takes place in a simple, pixelated environment where players control a character that must move horizontally across the screen.
The objective is to navigate the character through a stream of falling obstacles, avoiding being hit by any of them. Each hit results in instant failure, and the goal is to survive as long as possible without being struck. The game runs in the browser and does not require any downloads or registrations, making it accessible directly through the player's web browser.