With the Season 4 Reloaded update, the Call of Duty: Warzone playlist received a new game mode called Mutation Resurgence, along with some changes to the Popov Power POI in Urzikstan. Additionally, a new Bunker 13 Easter Egg was also added; here's how to solve it to unlock the Bunker Buster weapon charm for free.
NEW Bunker 13 Easter Egg in Warzone – Easy Guide
Bunker 13 can be visited in any game mode that is on the Urzikstan map (e.g. Battle Royale, Mutation Resurgence, or Plunder). Entering the bunker is quite simple, but you will need a Bunker Keycard (see image) to unlock the reward. The best way to get this item is by completing an Upload Intel contract.
Once you have a keycard, head straight to the Popov Power Plant in the northern region. Plunder is the best mode for this challenge, as there is no collapsing safe zone restricting your movement around the map. However, you may have to compete with other players who are trying to solve the same Easter Egg. At the marked point (see image above), you’ll find a submerged tunnel entrance. Follow the instructions below to reach Bunker 13 in no time.
Bunker 13 has various supply boxes and other loot items that you can take with you to win the match. You haven't used the keycard yet, but it is required for the next and final step in solving the Easter Egg.