ECHO

ECHO is a game of sound and darkness for the Commodore 64.

You have no eyes. The cave is pitch dark. Hold Z and you call out like a bat: the echo tells you how far the walls are, and for a moment the rock lights up where the sound touches it.

But every call is a beacon. Crawlers, bats and lurkers hunt by sound, and they come for the place you called from. Call, let go, move. Drop a pebble to lure them away. Keep your heart calm, because up close a racing heart can be heard.

Gather every crystal in the cave to open the gate. When the last one is taken, the cave starts to fall. Run.

• 24 caves, from first steps to a boss that hears everything
• Six creatures that hunt differently: one steals your echoes, one cannot hear at all and hunts heartbeats instead
• Stalactites to ring as lures, rubble that clatters, ledges that crumble, caves that flood
• Echoes tuned to a pentatonic scale: walking past walls while calling plays a tune
• Passwords, stars, a score, and an "only by ear" mode once you escape

Play

Play the demo above in your browser: the first 6 caves (needs a keyboard).

The full game is the download: Windows and macOS versions include the VICE emulator and start with a double-click. echo.d64 runs on any C64 emulator or a real PAL C64. The manual (PDF) tells the story, explains every creature and cave, and ends with how the game works inside.

Keys: arrows walk · Z (hold) sonar · X pebble · C dash · A echo bomb

macOS: the first time, right-click ECHO and choose Open (it is not from the App Store).

Credits

Written in 6502 assembly. The downloads run in VICE 3.10 (GNU GPL v2; its source code is one of the downloads). The web demo runs in EmulatorJS (GNU GPL v3).