The Wunderwaffe DG-2 dates back to the original Call of Duty World at War. Fast-forward 15 years, the players of Modern Warfare 3 have the opportunity to use this fan-favorite once again in the lands of a Zombie-overrun Urzikstan.
Modern Warfare 3 Zombies: How To Get The Wunderwaffe DG-2
Besides retrieving the Wunderwaffe DG-2 from the mystery box, there's only one other method to receive this Wonder Weapon. That is by completing all the story Modern Warfare Zombie Story Missions until unlocking Act III; Tier 4 mission "Holdout."
The mission "Holdout" requires players to complete an "Outlast Contract". This task looks like the satellite symbol on the map, once activating the symbol your task is to kill fifty Zombies in the outlined satellite space. The task objective specifically is "Remain in the environment until Analysis progression reaches 100%."
Once completing this mission, players will unlock a rift that spawns a 100% spawn chance WunderWaffe DG-2 Plans (schematic) that players can collect.
This schematic allows permanent usage, with players being able to craft the Wunderwaffe DG-2 every 48 hours. Unlike other weapon schematics that are single-use items, the Wunderwaffe DG-2 is worth unlocking because it's permanent, however, you will have to complete a huge chunk of the Zombies story to earn your Wonder Weapon.