This is a comprehensive list of all side easter eggs (therefore excluding anything in direct association with the main quest or map flow, such as the buildables) that I could currently find. Feel free to comment additional findings below!

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Find and knife 3 glowing white perk bottles in sparking blue arms around the map!

1. SPAWN. Laying on an edge wall atop the map, in front of a generator.
2. WATERFALL. Jutting from the side of a big tree stump in a puddle of water.
3. MINES. Protruding from a big aetheresque crystal in the wall, near the Paladin sniper wallbuy.

After knifing the bottles (may take some jumping, it's a bit finnicky), they will disappear. After the third one, a keeper will spawn behind you and drop a free perk powerup!


Make a wish!

1. Outside of the saloon Throw a grenade at the fountain so that it explodes next to it, causing the statue atop to begin sparking with electricity.
2. In the town area Search for a tiny gold coin atop various surfaces (tables, counters, crates, etc.) inside and around the buildings. There is no prompt for the coin. Known locations:

• Inside the Mercantile, on the counter to the right of the cash register.
  
• On the second floor/roof of the Mercantile, on a table next to some crates.
  
• Inside the Bank, on three crates to the right of old filing cabinets.

3. Back at the fountain Toss the coin into the fountain. A keeper will spawn behind you and drop a free perk powerup!


"Et tu, Brute?"

This is less of an easter egg and more a random spout of luck; and by that I mean, extreme luck because I've only ever encountered this once and it was very early in my first ever playthrough of the map.

Killing a warden has a chance of dropping a free perk powerup!

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Find 3 teddy bears and interact with them!

1. Above the first buyable door to the Buried section of the map, beside the Saug 9mm wallbuy.
2. Nearby the burnt down barn where Vulture Aid is; on a ledge above a purple 115 rock and across from a hanging water tower/silo.
3. In the mines, sitting in a crashed minecart at the center of a three way intersection, in front of a big aetheresque crystal in the wall.

This can be activated repeatedly in one game. Known songs:

• "115"
  
• "Archangel"
  
• "Ace of Spades"

Find 3 toys and interact with them!

1. In PAP, a tiny rabbit doll impaled on a spike to the direct left of the machine.
2. In Maintenance, (behind Stamin-Up) a tiny monkey doll to the moderate left of the door labeled 'Gardens'.
3. In Arrivals, a small Samantha music box on a crate to the right of the inactive teleporter/portal gate.

This can only be activated once per game.

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Buy my book to become a killionaire in only two easy steps!

Kill zombies.
Acquire 350 total zombie kills to unlock the OIP. An animation and sound will play when completed, and an orange fist will appear in the menu.

Kill more zombies (but melee this time).
Acquire an additional 50 zombie kills using the OIP. An animation and sound will play when completed, and a purple fist will appear in the menu.


Wield the classic weapon for free! (it's actually good surprisingly)

Obtain the badge.
Nearby the tree stump in a puddle, a set of crates will have a glowing sheriff's badge sitting on it. Interact with the badge and it will float slightly into the air. Then fill it with zombie souls. After killing around 20 zombies near it, the badge will descend back down for you to collect.

Return to owner.
In front of the entrance to the saloon, there are two graves alongside the building. One of them will have a skeletal hand sticking from the ground - give the badge to the arm, and in a few seconds time, it will gift a key to you.

Unlock the cabinet, sharpshooter.
Inside of the saloon, to the back left corner beside the stairs, open the cabinet and obtain your free M1 Garand (it's only free the first time). Congrats, you're a real cowboy now!


Would it be ominous for me to tell you to sanitize yourself?

In R&R, there are two small side rooms opposite of each other. Entering a room and turning around, to the immediate left of the door is a tiny pump bottle attached to the wall. Interacting with it seems to give you 100 points. The same can be done with the one in the room across. I believe that it is supposed to be a hand sanitizer bottle and a joke/reference to COVID-19 quarantine conditions.

It only seems usable once (I waited for five minutes mashing the button on it and then gave up) but I could've sworn I saw it give me 200 points once, so there's a chance it has some time reset or stipulation to give more points.


The easiest easter egg on the list because it doesn't go off the rails!

Open the Mines!
Located in the Buried/Western section of the map, find and open the mines.

Stand on the tracks!
Look for a signpost hanging on a wall that displays a skull. Run all the way down the tracks to the opposite wall (nearby a big crystal with an arm jutting out) and turn around, standing on (or near) the tracks and facing the skull in the distance. Then simply wait till you hear an activation noise. You may need to walk away and come back a couple times to make it activate.

LOOK OUT!
A horn will blare and a ghostly train will come barreling toward you! But don't worry; besides a little jolt and shaky screen, it'll just phase right through you.

Only occurs once per game.

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The Spooky Noises!
There are two objects that can be interacted with to cause spooky noises to begin playing. I am currently searching for a potential third one. The objects are:

• A skull sitting on a stool immediately to the right when entering Power.
  
• A hanging torso in the burnt down barn.

Four Bearmen of the Apocalypse
There is a fourth, non-usable, teddy bear in Maintenance, on a bench to the far left of Stamin-Up.

Suspicious Saloon
The saloon is filled with suspicious items, such as blue bottles, snowglobes, and a weirdly lit book with tiny dragon eggs next to it. But I want to specifically focus on two objects on the top floor: a zombie head with a top hat on and a jack in the box. The former is an unusual addition and the latter is suspicious on the basis that a lot of other toy-related objects in the map have been easter egg related.

IDM IDK
This one is more of a wild speculation, but it is a very real possibility that the IDM could drop something more significant than power-ups. However, I do not have any leads on how this would possibly be done.

Their Grave Mistakes
In the town area, there are three wooden graves, with inscriptions, lining a wall. These are assets from a BO3 multiplayer map called "Outlaw" (remake of "Standoff"). However, there could still be an easter egg tied to them because their location is slightly strange. In that potential case, I would guess it would be tied to the 'tales' being told in the inscriptions. This could also possibly be tied to the spooky noises.