Another quick step, yay! Now that the fire is out, the Pack-a-Punch machine allows it to upgrade the Sentinel Artifact you obtained in an earlier step. Place it in the machine, upgrade and retrieve it.
Call of Duty Zombies (CODZ) is a fan-managed gaming community centered around the popular Call of Duty franchise with central focus on the Zombies mode. Created in 2009, CoDZ is the ultimate platform for discussing Zombies theories, strategies, and connecting players.