CAIRNKEEP: Every Defeat Closes the Road

CAIRNKEEP is an original true fine-pixel cairn-building maze tower-defense puzzle. Arm West, East or Crown Watch for the current stable raider. That raider commits to the current shortest road to the gate. The armed Watch fires at the first road cell inside its public range; the defeated body becomes a permanent cairn on that exact cell before the next raider searches for a path.