Metroid
You supply your own Metroid (USA) dump. It is read in the browser and never uploaded. ROM body sha1 fdbfc7871962f72a1ef57e5a7e456164fb93430b, crc32 70080810, 131072 bytes; a plain iNES or a NES 2.0 header both work.
Files are read on this device. They are never uploaded.
Keyboard and mouse recommended.
The game downloads only after you press Play. Sound starts off.
Controls
| Arrow keys | move, aim up, morph ball |
| X | A (jump) |
| Z | B (fire) |
| Enter | Start |
| Shift | Select |
| Gamepad | standard mapping |
Metroid has no battery: the real cartridge continues from a password, not a save file. This build instead keeps an automatic save state in your browser, under this site, keyed to your ROM's own hash, and restores it when you return. It is a save state, not a save file. Clearing site data removes it, and the footer has a button to discard it. Save inside the game before exporting a backup. Clearing browser data can erase progress.