Rimworld Zombie Apocalypse is a mod that adds Zombies to the sci-fi colony sim "Rimworld". Zombies are mindless killers who attack anyone, whether friend or foe. They have an infectious bite which is fatal to anyone unlucky enough to let themselves get bitten, and anyone who dies to a zombie bite will be reanimated as a zombie themselves and add to the ranks of the zombie hoard. If that doesn't sound bad enough, in the Zombie Apocalypse incident the zombie virus goes airborne, infecting everybody. Once the virus goes airborne all corpses, regardless of their cause of death, will eventually be reanimated as zombies. These things add up to make zombies an interesting and unique challenge to face in the Rimworld universe.
This was a quick demo of the behavior of Zombies in my Zombie Apocalypse mod for Rimworld. The mod has changed a lot since this was recorded, but you can see examples of zombies popping up out of graves, and dead colonists/raiders turning.