Opening ad? If a black screen with a countdown appears, click SKIP in the bottom-right corner — the game starts right after.
Click the play area once so the game can read your keyboard. Arrow keys or WASD move, Space jumps or fires, and the on-screen pad appears on phones.
Blockscape Io runs straight in the browser tab — nothing to install, no account, no paywall. Progress is kept by the game itself in this browser.