Classified — Black Ops 4 Zombies Easter Egg Guide

Buy down from Main Offices to South Laboratories and throw the power switch behind the Soda perk area. This activates the elevators, teleporters, perk machines and every buildable/quest trigger on the map.

Tip: nothing else on this list — teleporters, amplifier, Pack-a-Punch, Cold War Remedy — will respond until power is on.

Four DEFCON switches raise the alert level (DEFCON 5 → 1) and power the teleporter network. Press all four in any order to charge the network, then step into the Server Room rear teleporter — with the switches set it drops you in the hidden Panic Room, where the amplifier component sits on a desk.

• DEFCON switch — Server Room, left side of the room
• DEFCON switch — War Room Lower, left of the elevator to the Labs
• DEFCON switch — War Room Upper, right of the elevator to the Offices
• DEFCON switch — War Room Upper, right of the Spitfire wall-buy

Gather three parts, build at the Central Filing (or Weapon Testing) bench, then carry the finished Signal Amplifier to the small teleporter in War Room Lower Level and install it on the pad.

Solo vs co-op: any one player can carry and install the amplifier; co-op just splits the part-collection legwork.

• Teleporter pad — Main Offices: beneath the teleporter desk, on the fallen desk, or left of the Brew machine (one of three random spawns)
• Wires — Morgue: on the chair right of the box location, on the corner countertop, or on a body chamber (one of three random spawns)
• Amplifier core — Panic Room: on the desk after you arrive via the Server Room teleporter

With the amplifier installed, set the alert back to DEFCON 5 (cycle the four switches until the board reads 5), then step into the large centre teleporter in the War Room. Instead of the Panic Room it now sends the team to Groom Lake / Area 51, where Pack-a-Punch lives (standard 5,000 per weapon). The Server Room teleporter still reaches the Panic Room after the amplifier is in.

Tip: if the centre teleporter still dumps you in the Panic Room, the amplifier isn’t installed or the board isn’t at DEFCON 5 — recheck both, then re-enter.

Collect three shield parts and build specifically at the Weapon Testing bench — that corner is the map’s high-round anchor. The Riot Shield both blocks the lane and doubles as a melee/point tool.

• Gun assembly — Central Filing part pool
• Base — War Room Lower part pool
• Window — South / North Laboratories part pool

This is the free Winter’s Howl (Project Skadi) quest. First, charge the window between the Escargot wall-buy and the Brew machine in Main Offices: hold the interact five separate times (a voice speaks for ~20–40s each time and Nova 6 gas Crawlers spawn in). Then collect four aerial-photo codes — each shows four randomised digits unique to your match — and enter them at the flashing-picture keypad in War Room Lower in the fixed order below. A green light per code and the “Project Skadi Retrieved” line confirm success. Finally, teleport to Groom Lake and stay for three full rounds; the barriers left of Pack-a-Punch open and the blue case holds Winter’s Howl.

Per-match codes (no solver): the four numbers are randomised every game and map directly to keypad digits — there is no cipher or arithmetic. Read what your match shows and type it; never reuse a number from a video.

Solo vs co-op: the quest is fully solo. In co-op only the player who picks up Winter’s Howl from the case gets the weapon (and the trophy) — everyone else must grab their own on a later run.

Enter the codes in this fixed order: 1) Shi No Numa, 2) Der Riese, 3) Shangri-La, 4) Kino der Toten. The collection order doesn’t matter; the input order does.

• Der Riese photo — take the key from the box opposite Cola in War Room Lower, use it on the central Main Offices desk drawer, and read the digits behind the Der Riese picture
• Shangri-La photo — with power on, throw a Frag (or fire a Pack-a-Punched explosive) behind the metal container with the yellow ‘Attention’ sign at the South Laboratories barrier near Weapon Testing; the photo teleports beside the window
• Kino der Toten photo — in the Panic Room, interact with the flickering bottom-row TV (some guides say move the TV) to reveal the code
• Shi No Numa photo — with a Pack-a-Punched weapon, shoot the Deserted Hallway nameplates in order George Washington → Benjamin Franklin → Alexander Hamilton → Abraham Lincoln; Washington’s plate lifts to reveal the digits

Classified’s “main quest” has no final interaction: finish round 149 and the round-150 cutscene plays automatically. Set up the Weapon Testing bench corner with the Riot Shield facing the single approach, keep a large point reserve for shield replacements, and cycle your equipment/specialist behind cover.

Core rule: replace the Riot Shield before it breaks — a fresh shield costs points, a broken one costs the run. Buy while the old shield still protects the interaction.

Loadout: Ragnarok DG-5 specialist, Wraith Fire, Equip Mint, and perks/modifiers such as Victorious Tortoise, Stonecold Stronghold and Timeslip. Winter’s Howl or a PhD-Slider Hellion is a strong secondary control tool between cycles.

Uncertain: exact per-round timings and enemy counts vary with player count and patch — trust the round-150 cutscene cue, not a stopwatch.