Completing the main quest on Der Eisendrache stands as one of the most rewarding experiences in Call of Duty Zombies history. Known formally as "My Brother's Keeper," this quest requires players to coordinate weapon upgrades, complete time-travel puzzles, and defeat a formidable final boss. Mastering every step of this journey ensures you can clear the map efficiently whether playing solo or with a full squad.
Initial Setup and Weapon Upgrades
Before attempting the main quest steps, players must power up the castle and feed the three dragon statues scattered across the map. Once the dragons consume enough zombies, you can claim the Wrath of the Ancients bow from the Undercroft tomb. Players will also need to construct the Ragnarok DG-4 gravity spikes by acquiring parts from Panzersoldats, the Death Ray, and the rocket test area.
Activating Wisps and Time Travel
The main quest truly begins when you shoot the teleporter prongs with an un-upgraded bow until they glow. This triggers a wisp step where team members must use upgraded bows to shoot four electrified items around the map within a single round. Successfully hitting all wisps allows the teleporter to send players back in time to retrieve a blue vial, fuses, and a safe combination.
Repairing the Death Ray and Collecting Souls
After returning from the past, insert the fuses into the Death Ray machine and set its display console to protect mode. Play the computer memory game at both the castle and rocket platform to drop a re-entry pod containing a golden vril rod. Returning to the Undercroft allows you to spawn a ghost keeper who will move to four locations, requiring players to charge him with souls using specific elemental bows.
Confronting the Keeper Boss
Once the keeper is fully charged and the pyramid is restored, place the Ragnarok DG-4 on the blue anti-gravity tiles to enter the boss arena. During the fight, avoid the Gatekeeper's devastating shock attacks by hiding behind the stone pillars. Plant your gravity spikes under the boss when he moves to the center, then concentrate all fire on his exposed yellow chest to win the battle and complete the quest.
