Matryoshka Doll Relic Tutorial - Black Ops 7 Zombies

Salvage drops are cut down.

Map: Astra Malorum | Tier: Sinister | Difficulty: Easy

Cursed requirement: Cursed Mode Tier 1, 2, or 3 required.

Portal: Machina Astralis, by the Cryopod.

Save note: Safe after Mars is open and before round 40.

Unlock steps

Open the Mars portal before round 40.
On Mars, place C4 on the three meat piles around the lower center stage.
Train a large zombie horde onto the stage before detonating.
Detonate the C4 when the horde is centered and the stage is clear enough for you to survive the blast window.
After the detonation registers, leave Mars and check the Machina Astralis portal area.

Zombie kills only count while a Field Upgrade is active. Waves 1, 3, and 4 build progress; later HVT zombie waves can include Uber Klaus and OSCAR.

Opening the Mars portal before round 40 keeps the high-round setup shorter and safer.
The trigger appears to care about a meaningful zombie group kill rather than a single cleanup explosion.
Aether Shroud is the easiest progress button because the active window lets you kill zombies without taking much return fire.
Frenzied Guard is the stronger co-op or safety option if you need armor and zombie control.
Do not waste the Field Upgrade on low-density spawns. Gather a wave, activate, then spend the full window.