Black Ops 7 Zombies: Astra Malorum — full main quest Easter egg walkthrough

Astra Malorum is Black Ops 7 Zombies' outer-space map, and one of its most layered main quests: it swaps the upgradable truck of the launch map for a roaming boss called OSCAR that can't truly be killed. Here it is in five phases.

Phase 1: Power, Pack-a-Punch and the Harmonic Oculus

1. Follow the objective markers to restore power and unlock Pack-a-Punch.
2. In the Observatory Dome, activate the Harmonic Oculus, the ancient device that runs the observatory's core systems. Nothing else in the quest moves forward until it's running.
3. Find the inactive Telescope in the central Observatory room and track down its missing components: one on the second floor, inside the Machina Astralis, next to a corpse; another in the Luminarium, the tiled room with planet models (the door costs 1,250 Essence), again beside a corpse.
4. Bring both parts back to the Oculus and install them. A 45-second defense begins — hold off the horde until it stabilizes.

Phase 2: OSCAR and the LGM-1 Wonder Weapon

1. Collect the three contraption parts that activate the map's traps. The map's Wonder Weapon, the LGM-1, is required to continue.
2. Kill OSCAR, the roaming boss that tracks you across the map, three separate times, using a different trap each time. He respawns after every kill.
3. After the third kill he explodes and the whole squad is transported to Mars.

Phase 3: Mars

1. Head through the gate in front of you and drop into the courtyard below.
2. Acquire the Ascendant Eye and place it on its statue.
3. Use the LGM-1 to shoot the tops of the pillars. Another step has you shooting down incoming objects before they reach a portal while zombies pressure you.
4. A brain item is placed at an altar at the back of the map, next to the portal that returns you to Astra Malorum.

Phase 4: Back in the observatory — the puzzles

1. Valves: shoot the five steaming mechanisms spread around the Observatory Dome, including near the portal and beneath the platform holding the Oculus and Pack-a-Punch.
2. Planet code: a recording lists planets. Convert each to its number by distance from the sun (Mercury 1, Venus 2, Earth 3…) — so Venus, Earth, Neptune gives 238.
3. Archive of Orbis: count how many of your reading-list books sit on each wall, then interact with the matching busts the corresponding number of times.

Phase 5: Caltheris

1. Return to the observatory and interact with the organ. Your screen flashes white when the final boss is ready.
2. Interact with the brain jar on the machine. A short lockdown begins — defend the brain against waves of zombies.
3. Fight Caltheris, a four-phase boss with homing lasers and area attacks. Take down its shield first so you can deal damage, and kill zombies to charge the weapon that fires at it. Shoot its vulnerable spots, and expect a long fight.
4. Defeat it to trigger the ending cutscene. Cursed Relic hunting opens up as soon as the game registers the completion.