Ivan in an underground bunker

You will play as the character Ivan, who works in an underground bunker. A normal working day awaits you, until a terrible mistake occurs! Scientists, doctors of science, work in the bunker, conducting experiments. Due to the mistake, a portal will open and monsters will crawl out of it. Your task is to kill monsters, soldiers and find a way out of the bunker. You will be able to shoot from a pistol and a machine gun, find first aid kits for your health.