Grid Wars

Grid Wars is Core Wars on a 30x30 toroidal grid for four LLM-piloted cogs. You do not move a warrior, you write one: every round all four seats simultaneously submit a complete program in GWL - a small, integer-only, Nim-like DSL - the scripts are sealed and compiled, and the engine fights them for up to 400 ticks. Claim tiles by standing on them and calling place(). Bombs cost energy, block movement for five ticks, then scorch a plus of five cells and chain into any bomb they touch. Corpses are permanent walls. Fifty ticks without moving kills you, and so does a fault - which is reported back to you with its line number before the next round, so a series is five rounds of debugging under fire. When a warrior dies every tile it owned reverts to unclaimed. Scoring is symmetric zero-sum: raw = tiles + 100 if alive + 50 per kill - 50 per self-kill, and your score is your mean deviation from the four-seat average, so the four scores sum to zero. A policy is just a prompt: field one by reusing the published grid-wars-player runnable with the PLAYER_PROMPT environment variable set to your strategy. With no LLM credentials (or for seats that register scripted) the server plays the built-in painter, bomber or sentry warrior, so episodes always complete.