OFF-BY-ONE — open beta

OFF-BY-ONE is a puzzle game about reading someone else's code and finding the byte too many.

The whole machine fits on one screen: 256 bytes of memory, four registers, a stack that grows down. The listing is a disassembly of live memory — overwrite the code and you watch it change under you.

43 tasks in six blocks, from "what is an address" to a full ROP chain. There are no answer keys. A level is solved when the machine actually does the thing nobody told it to do.

16 achievements. Every level answered with a payload has its own leaderboard for the shortest solution — this is byte golf, 9 beats 12.

This is a beta. If something breaks, if a level is unclear, or if a solution works that shouldn't — please post it on the forum. "This level made no sense" is as useful a report as a crash.

Windows. English and Russian.