Modern Warfare 3's open-world zombies mode expands on the Outbreak mode introduced in Call of Duty Black Ops: Cold War. In the Zombie infested Urzikstan of MWZ, players will encounter toxic Aether Nests, marked by an indicator on the Tac-Map that looks like a small puff of gas or smoke. If players can clear the nests, they'll be rewarded with a variety of loot - here's how to take out an Aether Nest.