Quadremor

In the 23rd century, humanity's advances made interplanetary colonization and interdimensional travel possible. Exploration of other dimensions led to contact with friendly species and a wealth of valuable data — until one dimension proved fatally hostile. Monsters slaughtered an entire expedition, assembled into an army, and poured through an open portal. After two weeks of fighting, humanity was nearly wiped out. The monsters retreated to their home dimension, not knowing that you — one of the last surviving mercenaries — followed them. You are now inside Quadremor, a hostile multiverse full of creatures that want every other race dead or enslaved. Your mission: kill them all, and make sure nothing from this dimension ever reaches our world again.