No-Sapien

From 2speccers2tools wiki

Dysentery

Kills all sapient species on 2s2t except on Cube (the continent) and the horrible rectangle tundra, and prevents them from coming back as it can exist as a ‘benign’ soil microbe. The one exception were the Microscope sophonts of Beans, who survived by being sheltered within their Citadel homes.