Conquering the "Harbinger of Doom" Dark Ops Challenge in *Call of Duty: Black Ops 6* Zombies requires eliminating 100 zombies with a single killstreak—a feat achievable with strategic planning and execution. Killstreaks, powerful support items, are your key to success.
Best Maps and Modes for the Harbinger of Doom Challenge
Black Ops 6 Zombies offers various modes (Standard, Directed, Jingle Hells), but Standard mode provides the necessary large zombie hordes. For optimal killstreak deployment, choose maps with ample open space. Terminus' Shipwreck and Liberty Falls' Pump & Pay spawn area are excellent choices.
Top Killstreaks for Maximum Zombie Destruction

The Chopper Gunner and Mutant Injection are the most effective killstreaks. The Chopper Gunner unleashes a devastating minigun barrage from above, while the Mutant Injection transforms you into a powerful Mangler. Both offer invulnerability, crucial for maximizing kills. These can be crafted at a workbench for 2500 Salvage or obtained through chance encounters with special enemies, S.A.M. Trials, or Loot Keys.
Strategies for Success

Aim for rounds 31-40 for maximum zombie density. Activate the Rampage Inducer to further boost enemy spawns.
Mutant Injection Strategy: Gather a large horde in a confined area (Terminus' Rec Yard, Liberty Falls' Backlot Parking, or Citadelle des Morts' Oubliette) and unleash the Mutant Injection. Focus on aggressive melee attacks.
Chopper Gunner Strategy: Assemble a large horde in an open area (Terminus' Shipwreck, Liberty Falls' Backlot Parking, or Citadelle des Morts' Town Square) and call in the Chopper Gunner for aerial annihilation.
Mastering these strategies will significantly increase your chances of completing the "Harbinger of Doom" Dark Ops Challenge and claiming your reward.