Step 1
Power & Laptops
Turn on the power and activate Pack-a-Punch by defending the three generators.
Activate three laptops scattered around the map.
Laptop Locations
Right outside the room containing Stamin-Up (corner of the platform).
Right outside the room containing Quick Revive (corner of the platform).
Upstairs from the dock area (right next to the stairs after going up).
Step 2
EMF FOB & Multiphasic Resonator
Obtain a Dead Wire mod on your gun and ride the elevator that has the Pack-a-Punch machine on it. It is highly recommended that you ride the elevator from bottom to top and not the other way around.
Shoot the fuse boxes inside the window around halfway up, and there will be sparks leading to another fuse box. Follow the cable and shoot the chain of fuse boxes until the research office opens.
Shoot the zombie inside the secret room for an item called the EMF FOB.
Go to the Sea Tower (room containing the Armor Station and Elemental Pop) and open the briefcase with the severed hand attached to it to retrieve the Multiphasic Resonator.
Go back to the research office and put the Multiphasic Resonator into the computer. Three sticky notes will appear on the computer, telling you which symbol corresponds to X, Y, and Z. Look on the whiteboard to get the numerical values corresponding to the three variables.
Step 3
Equation Solver
Solve the three algebra equations on the whiteboard — each one provides you with two digits out of the six-digit code.
Input the six-digit code into the computer. Wait until the resonator is calibrated (might take two or three rounds) and retrieve it. Don't forget to grab the resonator off the computer!
Step 4
Three Islands
Now you need to head to three different islands and complete a mini quest at each one.
Castle Rock Island (Blue Orb)
Head to Castle Rock Island (right-hand side of the map) and you will find a glowing blue orb. This orb only spawns if you retrieved the resonator — if it isn't there, you forgot to pick it back up. Go back to the research office and pick it up.
Place the Multiphasic Resonator under the orb and zombies will spawn. Periodically, the orb will zap a zombie, making it glow. Kill the glowing zombie and it will drop a small spark.
Take the spark and run into the orb to place it there — you cannot sprint while holding the spark, so make sure your teammates protect you. After collecting three sparks, the mini quest is finished; take the resonator and move on to the next island.
Crab Island (Green Orb)
Head to Crab Island (large island at the bottom of the map) and repeat the mini quest, feeding three sparks into the orb. The orb will be green this time.
Temple Island (Purple Orb)
Head to Temple Island (small island in the top-left corner of the map) and repeat the mini quest. The orb will be purple this time.
Reward
After completing all three islands, you will receive the AMP Munition, which allows you to craft the wonder weapon.
Step 5
Beamsmasher & Hard Drive
Go back to the research office, and on the workbench there you can craft the Beamsmasher wonder weapon.
Note
Only one person can craft the Beamsmasher, so make sure you give it to your best player!
Look for a tentacle trap that has a broken crate and a red keycard underneath it — only this specific tentacle trap will give you the quest item. Activate this trap and shoot the tentacles with your newly acquired Beamsmasher, and a hard drive will fall out.
Take the hard drive to Peck and give it to him (Peck is the person standing behind the bulletproof glass window inside the spawn location).
Tentacle Trap Locations
There is a tentacle trap in the room containing Juggernog, and two more tentacle traps above the two doors that connect the lab area to the caves.
Step 6
3-Digit Code & Nathan
Now you need to find a 3-digit code.
Digit Locations
First digit — In the interrogation room, right next to Quick Revive. There is a small clock in an inaccessible area, and the digit is the hour hand of the clock. (Remember, the hour hand is the shorter hand!)
Second digit — In the mess hall (the room containing the Arsenal Station). There will be a playing card pinned to the message board — the number on the card is the second digit.
Third digit — In engineering, the room containing the crafting bench. The third digit is the number of days since the last injury.
Head down to the lab. In the center of the lab is a giant cylindrical chamber containing Nathan (Maya's brother). Input the three-digit code, and have all teammates turn the valves on the cylinder at the same time. Nathan will be freed, and the lab area will enter lockdown mode, preventing you from leaving.
Boss Fight — Nathan
Nathan is a mini boss you'll need to kill. It's recommended you have at least 3-4 perks and a Pack-a-Punch level 2 gun of blue rarity or above, as this fight is very difficult. It can be extremely easy with multiple Pack-a-Punched wonder weapons on your team, but under normal circumstances expect a bit of a struggle.
Step 7
Node Connectors & Pipes
After killing Nathan, dive into the water — under one of the bridges there will be a golden keycard.
Head to the destroyed ship and enter through the destroyed sides. Head up the ladder and into a room.
Warning
DO NOT take the node connectors on the table until ALL teammates have entered the ship, as the door will close immediately if any node connector is taken — you might get trapped there by yourself!
The room will enter lockdown, and you must survive until it opens again.
Once your team leaves the sunken ship with the node connectors, use them to repair broken pipes around the map. Look for a pipe with a section missing and crackling with electricity.
Broken Pipe Locations
In my experience only two locations need to be fixed each game, but they're randomized. The broken pipe can spawn in: Crab Island (right across from the workbench), underneath the Sea Tower (around the bottom of the zipline), or in the tunnels next to Speed Cola.
Step 8
Hacking the Buoys
Head back to Peck (the person standing behind the window) and retrieve the hacking device. Head out in a boat and look for the floating buoys around the edges of the map.
Hold the interact key next to a buoy to start hacking it with your hacking device. A 2-minute timer will start, and you must find and hack the next buoy before time runs out. You need to hack three buoys total, and they're guarded by parasites (flying mosquitoes).
Note
Only the person who picked up the hacking device can do the hacking — it isn't shared across the team!
Final Step
Boss Fight
Upon hacking all three buoys, immediately run to the bio labs — a 5-minute timer will start. There are three bombs located inside the underground lab area which you need to defuse before the timer runs out.
Bomb Locations
Two are located on the lowest level of the lab, and one is located directly above the Melee Macchiato machine. Hold the interact key for a few seconds to disable them — make sure a teammate is protecting you. The bombs look like purple canisters embedded within walls.
Upon defusing all three bombs, enter the boss fight by interacting with the door next to Melee Macchiato. The boss is a giant octopus monster that will chase you with its tentacles if you stay in the water too long.
Preparation
It's recommended to max out as much as possible before attempting this fight — it's incredibly difficult and can take anywhere from 30 minutes to 1 hour. The optimal window is round 21 to about round 25; any later and you risk making things much harder for yourself. Bring at minimum a Pack-a-Punch level 2 weapon of purple or orange rarity. Craft Kazimir Devices, Monkey Bombs, and Self-Revives at the workbench if you have the resources. Chopper Gunners are extremely useful since they ignore boss resistances, so everything counts as weak-spot damage — get as many as possible. Ammo isn't a big issue, as there's an ammo crate inside the boss arena and zombies will typically drop ammo periodically. Constantly pick up armor plates dropped by zombies, and bring at least a level 2 armor carrier.
Phase Mechanics
When you get the boss below 1/3 health, he starts doing charged shockwaves that will instantly kill anyone who isn't hiding behind something. Jump in the water if you need to recover health — it's actually a very safe spot since zombies can't attack you there.
Weak Spots
Only shoot his glowing weak spots — shooting anywhere else barely does any damage. The glowing weak spots change locations periodically. Look for bulbs on his shoulders, his mouth, his eyes, and generally shoot anything that glows.
Upon killing the boss, the main Easter egg is completed. You'll be prompted whether you want to stay in the game or end the game. If you stay, you'll be given all perks, and a couple of weapons of legendary rarity or wonder weapons will spawn. You're free to farm zombies as you wish and extract at your leisure.