Battlefield 1

Battlefield 1
Completed

The Battlefield 1 ARG - Headphones and Morse code led to mysterious unlockable dog tags.
Type	Official
Creator	DICE
Discovered	2017-02-14

Main Page > List of Investigations > Battlefield 1

Back to the Top

This wiki page documents the ARG that is hidden in Battlefield 1. This page includes step-by-step instructions to unlock the secret A Beginning, A Conflict, An Omen, Angel Sighting, and Belly of the Beast dog tags, the An Escalation skin, as well as the Peacekeeper revolver and its associated service dog tag called An Awakening. Currently, the primary solving hub for this ARG is the Battlefield Easter Egg community, who have a Discord server here, a wiki here, and a YouTube channel here.

In addition to the main ARG/Easter egg which unlocks the secret dog tags and skin, there are several other prominent Easter eggs which have been discovered in the game:

Battlefield 1 Easter Eggs
Balloon House	A house kept aloft by balloons, referencing the movie 'Up'
Megalodon	A giant shark hidden on Fort de Vaux
Miscellaneous	Minor Easter eggs requiring little to no player interaction

(Note: Main ARG/Easter egg is disabled in password-protected servers!)

Headphones and Morse code

One pair of headphones is hidden on each map. The headphones are indestructible and can be located on every server, as long as they have not already been picked up. It appears that there are 5 spawn locations per map, although some of them remain undiscovered. The headphones can be picked up by any player by walking over them. Upon approaching a hidden telegraph station after having retrieved a pair of headphones, the player will hear some Morse code being tapped out. A player can carry only one pair of headphones at a time, and only the player wearing the headphones will be able to hear the Morse code when near enough to a hidden telegraph station.

Headphone Locations

Here is is a series of images which display locations of headphones and telegraph station on each map. In order to hear the Morse code, the player needs to pick up the headphones from one of the 5 locations on each map (It might be necessary to check all 5 locations before finding the headphones) and bring them to the telegraph station.

(Note: you can click each image to get a larger version.)

Amiens
Argonne Forest
Ballroom Blitz
Empire's Edge
Fao Fortress
Monte Grappa
Sinai Desert
St. Quentin Scar
Suez

When the headphones and telegraph stations were first discovered, the Morse code was meaningless gibberish. However, the contents of the Morse code changed in future patches.

Fall Update

On November 15th, Battlefield 1 received an update which changed the Morse code heard on all maps' hidden telegraph stations to the following:

.--. .-. . ...- .. --- ..- ... | -- . ... ... .- --. . | -.-. --- .-. .-. ..- .--. - . -..
.- .-- .- .. - | ..-. ..- .-. - .... . .-. | .. -. ... - .-. ..- -.-. - .. --- -. ...

PREVIOUS MESSAGE CORRUPTED
AWAIT FURTHER INSTRUCTIONS

Additionally, the patch changed the following:

Ballroom Blitz had a telegraph station and headphones added to it, whereas pre-patch it was the only map with neither
The spawn locations of many headphones on most maps were changed
The above Morse message now plays on loop until the telegraph station eventually explodes, although this appears to be buggy
Once the telegraph station explodes, headphones stop spawning on the map
Dying after having retrieved a pair of headphones will no longer cause a new pair of headphones to spawn
Only one pair of headphones will spawn upon the initiation of a round on each map

Winter Update

On February 14, the Winter Update was released. The Morse code changed again, to the following message:

GO STRAIGHT TO <location_name>. OLD METHODS COMPROMISED. MUST ACQUIRE NEW KEY. WILL MISS DROPOFF IF DELAY OR INCORRECT LOCATION.

Each user hears a different location name; locations are randomly assigned to players. There are 27 locations total: 3 locations on each of the 9 maps. In order to advance through the Easter egg, you need to know which location you are assigned; here is a tutorial (courtesy of Dunem) to help you read your Morse code. This is the list of locations, along with their respective maps, in alphabetical order:

AMIENS NEUF FURNITURE: Amiens
BALLROOM MAP VARENNES: Ballroom Blitz (Formerly ABBEY MAP VARENNES)
BUCKET MARSHLANDS FAW: Fao Fortress
CANAL KANTARA VASES: Suez
CASTELLO ISLE ADRIATIC: Empire Edge
CHURCH RUINS AMIENS: Amiens
COASTAL FORTRESS ADRIATIC: Empire Edge
CRATE JABAL JIFAR: Sinai Desert
CRATE SEREN VENETIAN: Monte Grappa
CRATE TRENCH CANAL: Suez
FERRO FIRE VENETIAN: Monte Grappa
HILL BARN ADRIATIC: Empire Edge
HILL TOWER CANAL: Suez
HOTEL CHECK PERONNE: St. Quentin Scar
LONGUEVILLE STATUE AMIENS: Amiens
LUGGAGE BASEMENT APREMONT: Argonne Forest (Formerly LUGGAGE BASEMENT VARENNES)
OUTPOST BARREL FAW: Fao Fortress
PANEL WATER APREMONT: Argonne Forest (Formerly PANEL WATER VARENNES)
PILLAR OUTSKIRTS JIFAR: Sinai Desert
PILLOW MAZAR JIFAR: Sinai Desert
RUIN VENTURE PERONNE: St. Quentin Scar
STATUES GARDEN VARENNES: Ballroom Blitz (Formerly STATUES GARDEN APREMONT)
STOVE TURRET VENETIAN: Monte Grappa
TRAVECY ATTIC PERONNE: St. Quentin Scar
TREE FORTRESS FAW: Fao Fortress
TREE TRAIN APREMONT: Argonne Forest (Formerly TREE TRAIN VARENNES)
VARENNES SERVANT BED: Ballroom Blitz (Formerly APREMONT RITZ BED)

The message will repeat until you move away from the telegraph station, at which point the telegraph station will explode. Each of the locations mentioned above has a symbol near it.

Symbols

The first symbols discovered at each location are difficult to find; they are small double arrows pointing to the left and right, and only appear when the player comes within 0.4 meters. A player will typically need to crouch or go prone in order to be able to see their symbol. Additionally, players can only see the symbol at the location they've been "assigned" to. When examining a symbol up close, a distinct sound is played (video). Pictured below are all 27 symbol locations, sorted by the map they appear on (maps made by Darrel).

NOTE: If you're having trouble finding your location with the images below, Jambajeww has made a video guide for all 27 locations, with timestamps for each location in the description of the video.

Amiens
AMIENS NEUF FURNITURE
CHURCH RUINS AMIENS
LONGUEVILLE STATUE AMIENS
Argonne Forest
LUGGAGE BASEMENT APREMONT
PANEL WATER APREMONT
TREE TRAIN APREMONT
Ballroom Blitz
BALLROOM MAP VARENNES
VARENNES SERVANT BED
STATUES GARDEN VARENNES
Empire's Edge
CASTELLO ISLE ADRIATIC
COASTAL FORTRESS ADRIATIC
HILL BARN ADRIATIC
Fao Fortress
BUCKET MARSHLANDS FAW
OUTPOST BARREL FAW
TREE FORTRESS FAW
Monte Grappa
CRATE SEREN VENETIAN
FERRO FIRE VENETIAN
STOVE TURRET VENETIAN
Sinai Desert
CRATE JABAL JIFAR
PILLAR OUTSKIRTS JIFAR
PILLOW MAZAR JIFAR
St. Quentin Scar
HOTEL CHECK PERONNE
RUIN VENTURE PERONNE
TRAVECY ATTIC PERONNE
Suez
CANAL KANTARA VASES
CRATE TRENCH CANAL
HILL TOWER CANAL

Second Message

A triangle symbol discovered at the VARENNES SERVANT BED location

After a player discovers their symbol, returning to a telegraph station with headphones yields another message in Morse code. Additionally, the telegraph station's lights glow yellow instead of their usual white when broadcasting this message. The message starts with one of the above location names, but reversed:

<reversed_location_name> REMEMBER FIRST RULE. IF COMPROMISED L PILL.

An L PILL is short for lethal pill, a pill intended to be taken by soldiers to commit suicide rather than be tortured. Visiting the specified reversed location, the second location, yields a triangle symbol in place of the normal double-arrow symbol. The second symbol appears in the exact same spot that the first symbol may appear for other players.

Third Message

The third symbol that can be discovered (credit to Noizex)

After a player discovers the triangle symbol at their second location, returning to a telegraph station with headphones yields another message. This time, the telegraph station's lights glow purple. Here's the text of the message:

<atbash_cipher> SECOND RULE. ON SIGHTING. REPORT AND WAIT. INVESTIGATING ALONE COULD LEAD TO DEATH

Solving the Atbash cipher in the message yields another location from the list above. Visiting the third location leads to an arrow symbol pointing right.

Fourth Message

The fourth symbol (credit to Noizex)

Returning to a telegraph station after discovering the third symbol yields yet another message. This time, the telegraph station's lights glow green (previously, they glowed white, yellow, and purple for the first, second, and third messages respectively). Here's the text of the message:

<rot_cipher> THIRD RULE. IF TAKEN BY THE OTHERS DISCOVER MEANS TO COMMUNICATE TO HOUSE

Solving the ROT cipher with a key of 7 (N = 19) yields another location from the list of locations, leading to a fourth symbol, which is shown on the right.

Fifth Message

The fifth symbol (credit to Dexx)

After finding the fourth symbol, the telegraph station's light color turns transparent. This message begins with a location from the list of locations:

<rail_fence> FOURTH RULE. KILL ALL ON SAME TRAIL. REMOVE DOG TAGS AND REPORT TO HOUSE

To get the plaintext, the ciphertext must be reversed and decrypted using the rail fence cipher with 5 rails, and 0 offset.

Note that the previous symbol, the fourth symbol, is in the shape of a fence, which may be interpreted as a hint for the correct decryption method for this cipher (rail fence cipher).

The fifth symbol is a pattern of broken and unbroken dashes.

Note: the cipher on this stage can also be solved as an anagram.

Sixth Message

The sixth symbol, "Edward" (credit to Noizex)

After finding the fifth symbol, the telegraph station's lights turn to an orange color. Here's the content of the sixth message:

<double_cipher> MORSE MESSAGES BEING INTERCEPTED. BEGINNING FULL ENCRYPTION SOON

The "double_cipher" is comprised only of single dots and single dashes: E's and T's in Morse code. The cipher can be solved by converting the transmission into A's and B's, where A is a dot and B is a dash. Then decode the ciphertext (AABBABABBAA etc) using a Baconian cipher, then decode the output of the Baconian cipher with an Atbash cipher to obtain another location from the list.

Visiting the sixth location yields the sixth symbol: a series of horizontal and vertical lines with the name "EDWARD" prominently featured between them.

Seventh Message

The seventh symbol, "George" (credit to Noizex)

After finding the sixth symbol, the telegraph station's lights turn to a pink color. Here's an example seventh message, which is a Vigenère cipher:

PXCGRJIEWSVPIQPVRUIQJEJDPOEEJFEQXETOSWDEUDWHJEDLIVANVPMHOCRQFHYLFWLHZAJDPOEEJDPZWYJXWHED

This transmission is encoded via Vigenère Cipher with the key "Edward". It decodes to:

LUGGAGEBASEMENTVARENNESALLIESCANBECLOTHEDASENEMIESENEMIESCANBECLOTHEDASALLIESALWAYSUSEID
LUGGAGE BASEMENT VARENNES ALLIES CAN BE CLOTHED AS ENEMIES. ENEMIES CAN BE CLOTHED AS ALLIES. ALWAYS USE ID

In the example above, LUGGAGE BASEMENT VARENNES may be replaced with any of the locations from the complete list. Going to the specified location reveals the seventh symbol, which prominently displays the word "George" above a crude drawing.

Eighth Message

The eighth symbol (credit to Noizex)

After finding the seventh symbol, the telegraph station's lights turn to a lime color. Here's an example eighth message, which is an autokey cipher:

ONADIFZWMPTJSHJGXROUUEKUWFHGJHNWUYMESYQYXXFAWAUGQNMESY

This message decodes to the following, by using an autokey cipher with passphrase of "George" and alphabet key of ZABCDEFGHIJKLMNOPQRSTUVWXY:

HILLBARNADRIATICFINALBELIEVEEVERYTHINGREPORTEVERYTHING
HILL BARN ADRIATIC FINAL BELIEVE EVERYTHING REPORT EVERYTHING

In the example above, HILL BARN ADRIATIC may be replaced with any of the locations from the complete list. The eighth symbol, which is just the word "LONDON", will be at the specified location.

Ninth Message

After discovering the eighth "LONDON" symbol, the telegraph station's lights turn cyan. In a deviation from the normal structure of the Morse code, this cipher is identical for everyone:

ZQBRIPPQOHBFIUPEYLAZAMARZIOZDSYJB

After a long search, it was finally discovered that reversing the above ciphertext and using the reverse as input for an autokey cipher with key "LONDON" and custom alphabet ZABCDEFGHIJKLMNOPQRSTUVWXY yields:

PUKOOLYNOCLABLLIMDNIWWODAHSSTNAIG

If you reverse this output, it reads:

GIANTSSHADOWWINDMILLBALCONYLOOKUP

GIANTS SHADOW WINDMILL BALCONY LOOK UP

A Beginning

The final Morse code, once deciphered, directs the player to the balcony of a windmill on the map Giant's Shadow; specifically, the windmill nearest to the German Empire deployment. Standing on the balcony of the windmill and looking outward/slightly upwards (video) while waiting for exactly two minutes will trigger a courier pigeon to swoop past the player. The same dramatic sound effect heard when viewing the symbols will play, and it is a this point that a new dog tag becomes available to the player. The tag is named "A Beginning", and has the description "You've found something that does not belong to you.". It should be noted that a player will only be able to trigger the pigeon if their telegraph station is on the cyan lights stage (stage 9) - you cannot skip the previous stages. If the dramatic sound does not trigger when the pigeon passes, the process must be repeated until the sound is triggered. Some reports indicate that the sound will not trigger unless the pigeon passes through the player, touching them. Nonetheless, if the pigeon is flying past you, you are at the right stage and have completed the necessary prerequisites.

In addition to the dog tag, the player's telegraph station's lights will change to a red color. Another Morse code message can be heard with headphones, but at a lower pitch than before, and accompanied by eerie background noise and apparent screaming (video). The message decodes to:

MASTER MAN

The code repeats indefinitely. The meaning of MASTER MAN has yet to be determined, and the whispering/screaming noises in the background have yet to be clearly transcribed. It has been noted that the Morse code definitely has a space between "Master" and "Man".

One theory is that MASTER MAN refers to a radio operator, as shown below. As shown, he has access to telegraphs and colored light signals on a master control board. Through an in-game message by a DICE employee, we were told that "Red is a signal color", in response to queries about the telegraph station's red light.

Additional Resources

All the telegraph station's light colors:

Stage 1 (white lights)
Stage 2 (yellow lights)
Stage 3 (purple lights)
Stage 4 (green lights)
Stage 5 (clear lights)
Stage 6 (orange lights)
Stage 7 (pink lights)
Stage 8 (lime lights)
Stage 9 (cyan lights)
Stage 10 (red lights)

The following image was datamined after the release of the Winter Update patch on February 14, 2017:

Between its color channels, this image contains all of the symbols mentioned above.

Prise de Tahure Update

On July 20, 2017, another map was added to the game called Prise de Tahure. Located on the map were several records, along with a gramophone, much like in the Megalodon Easter egg. Bringing a record to the gramophone makes it play the Battlefield 1 theme tune. At this time it is unknown if the records and gramophone have another purpose.

Four Square Cipher

The code that appeared on Soissons, along with the hints above it

Also on July 20, a cipher was added to a pillar near the lake northeast of the Château on Soissons. Above it were several graphical hints, including the icon of the A Beginning dog tag that was unlocked earlier in the ARG. The text of the cipher is as follows:

YPIVEZKUSYRNHZELDWSOMSPXINALXGWNHACPLTVZPNCPLBRPVXYPTHWNHQALYG

When solved as a four-square cipher using the keywords of MASTER and MAN, and reversing the remainder of the alphabet, the cipher was decoded:

INSIDE THE CHATEAU WHEN ALL IS DARK THERE YOU GO AND YOU WILL FIND THE SPARKS

Lights Out

It was discovered that destroying every light source in the château on the Soissons map causes a mechanical sound effect to play. After doing this, the bases of the candle stands become interactable - players can switch them on or off. Interacting with candles causes the states of surrounding candles to switch, along with the position in that candle's cycle. There are a total of 7 candles in the château. Once all the candles have been illuminated, another mechanical noise is heard, which allows us to advance to the next stage.

The seven candles each switch the state of one or more others. When any candle is activated, the candles' functions would rotate one position counterclockwise (explained more here) around themselves. By activating a single candle seven times and recording the results, you can learn all of the switch patterns and know they are back where they started. With this knowledge it is possible (with some brain bending) to work out how to illuminate all the candles. This could of course be done with pen-and-paper, but there is an Excel spreadsheet (link may expire, made by Disposalist) as well as an app that may also prove useful.

Also, after pressing a candle seven times, only one candle's state will be changed. All candles go back to their original states after a candle has been pressed fourteen times.

Note: If you don't press anything for 4 minutes the candles will reset and the switch patterns will change!

Tile Puzzle

A map of the château, pillars, and statue, courtesy of TheRadGamerDan

One pattern of lit-up tiles in the floor of the château

The orientation of the sandbag pattern relative to the grid, courtesy of MozzyFX

After lighting up all the candles in the château and hearing the second mechanical noise, some wall panels on pillars on the outside of the château become interactable. There are 8 pillars on the north side of the château, and 8 on the south side.

To the northeast of the château, there is a statue sunk into the ground, along with concentric square steps leading down towards it. After the second mechanical noise is heard, a randomly-generated pattern of sandbags appear on some of these steps. They only appear while no one is near the steps. The goal here is to manipulate the floor lights inside the château so their pattern matches the pattern of sandbags around the statue.

The pattern of tiles inside the château consists of an 8 by 8 grid. At the beginning all tiles are turned off. Each individual tile can be manipulated using a pair of wall panels. There are 8 panels on the north side of the château, and 8 panels on the south side - each panel corresponds to either a row or a column on the grid. Pressing the pair of panels corresponding to a specific row and column cause the appropriate light to toggle on or off. For example, if you were to press the "2nd column" panel and the "4th row" panel, then the light in position (2, 4) on the board would be toggled.

However, there is a twist: the rows and columns the panels correspond to are completely randomized in each round (or pre-round). There is no grouping to the panels; for example, not all panels on the north side are the row-controlling panels. This randomization means that players need to use trial and error in each round (or pre-round) in order to determine which panels activate which rows and columns.

One method for accomplishing this is as follows:

Choose an arbitrary panel from one of the 16 panels outside the château. (You could start with the panel labelled '1' on the map shown above.)
Try pressing your chosen panel followed by another arbitrary panel. (Again, you could use the panel labelled '2' on the map.)
Check the light grid. If no lights have changed, pick a new panel as your second panel, and try pressing it along with your first one. Repeat this until a light changes on your grid.
Once a light on your grid has changed, note its position in the grid along with the panels you used to activate it.
Pick a different panel that you haven't tried yet as your second panel, keeping the first panel the same. Continue to try new combinations that include the first panel until another light is toggled.
By this point, you should have toggled 2 different lights, and you should have had 1 panel (the first panel) in common with both of those lights. The two lights you toggled will share either a row or a column on the grid.
The panel the lights had in common (the first panel) can now be associated with the row or column that contained the toggled lights. The other 2 panels you pressed can be associated with the intersecting rows or columns.
Repeat the whole process, starting with a different panel. Continue until every panel's row or column is identified.

Example:

Let's say we start out trying to identify Panel 1.
We try pressing Panel 1 and Panel 2, but nothing changes, so we move on.
We try pressing Panel 1 and Panel 3, and a light changes at position (1, 5) (first column, fifth row). We note this down and move on.
We try pressing Panel 1 and Panel 4, but nothing changes.
We try pressing Panel 1 and Panel 5, but nothing changes.
We try pressing Panel 1 and Panel 6, and a light changes at position (6, 5) (sixth column, fifth row). We note this down.
The two lights that changed were both part of the 5th row, and we pressed Panel 1 in both cases. Therefore, Panel 1 must be the button for the fifth row.
In addition, from the first light that changed, since we know that Panel 1 is the button for the fifth row, Panel 3 must be the button for the first column.
Similarly, from the second light, since we know that Panel 1 is the button for the fifth row, Panel 6 must be the button for the sixth column.

From here, determining the rest of the panels' functions by trying unknown panels with known ones is easy.

Note: If a given pair of buttons causes no change in the light grid, they must both either be for rows or columns, since they do not intersect.

Once each panel's functionality has been determined, matching the lights up with the sandbags is a fairly simple (if tedious) task. The sandbags appear on only some of the concentric steps, which correspond to square "rings" on the light grid. The position of the sandbags along each step indicates that the light in the corresponding location on the grid needs to be turned on. All other lights need to be turned off.

An example sandbag pattern is shown below:

A pattern of sandbags on the square stairs around the statue (up = northeast)
Fitting the sandbag positions to the 8 by 8 grid
The corresponding pattern that needs to be illuminated on the grid (up = west)

A Conflict

The "A Conflict" dog tag, awarded to the player that completes the tile puzzle

Once the tile/sandbag puzzle has been completed, a plume of black smoke appears, and the A Conflict dog tag is awarded to the player who activated the final panel - the dog tag is NOT awarded to all players on the server, only the person who completes the Easter egg! The dog tag has the same skull icon as the A Beginning dog tag, but is silver instead of bronze.

Note: The A Beginning dog tag is not required to unlock the A Conflict dog tag!

The dog tag's description is as follows:

The voices have been silent far too long.

Turning Tides Gallipoli Update

On December 11, 2017, the Turning Tides update was released for Battlefield 1. Little progress was made on this Easter egg until January 30, 2018, when mysterious Morse messages were added to the lighthouse on the Heligoland Bight map. These messages are only audible when the player is playing as the Infiltrator Elite class, and only one of these messages can be heard in any round.

CODE COMBINED WITH THE LOCATION NAME THEN TEXT SPLIT IN SIX. A PIECE HIDDEN IN EACH ZONE.
USE THE NUMERIC KEY TO PUT THE PIECES IN ORDER AND SEPARATE THE LOCATION FROM THE CODE. GO TO LOCATION AND USE THE CODE.
TO MAINTAIN SECURITY CHANGE THE THIRD ONE OFTEN. LOOK IT UP EVERY TIME YOU GET THERE.
THE LOCATION OF THE FIFTH ONE WAS CAREFULLY CONSIDERED.
18 TOTAL.
TOP TO BOTTOM.
AFTER YOU SEE YOU ARE DONE ENTERING THE CODE... HURRY.

Each message also ended with RELAY THIS MESSAGE TO OUR SIX OPERATIVES IN THE SNOWY REGIONS.

These clues were used throughout the Easter egg.

Skull Icons

A skull icon was discovered in all 6 maps from the In The Name of the Tsar expansion - the SIX OPERATIVES IN THE SNOWY REGIONS. Below are the locations of each of the skulls (credit to BFEE):

Tsaritsyn
CASE
Brusilov Keep
WEB
Albion
Appears above a switch, hidden behind a cupboard in a house. Pressing the switch is a step to reveal Morse code, which is unique for each player - it must be LOOKED UP each round.
Galicia
FEAR
Volga River
B█D
Note: its location was "CAREFULLY CONSIDERED" - the blacked-out letter is an A, since the skull appears near Control Point A.
Łupków Pass
No text, but standing in the southeast corner of the ruins causes a small orb in the opposite corner to flash out the following message in Morse code: TEST FAILED ANGELS LOOSE PROCTORS DEAD TRI ODIN NOLX ETYRE ODIN DWA. The Russian words at the end are numbers, translating to 310412.

Location and Code

The Sworbe Lighthouse on Albion

According to the Morse messages, the next task was to USE THE NUMERIC KEY TO PUT THE PIECES IN ORDER AND SEPARATE THE LOCATION FROM THE CODE. The numbers 310412, obtained from the final skull, specified the positions of letters that had to be taken from each word:

CASE
WEB
0
FEAR
BAD
DEAD

This produces the message SWORBE, the name of a lighthouse on Albion.

Additionally, the location had to be SEPARATED from the code; accordingly, the remaining letters were isolated. Because the Morse explicitly stated that there needed to be 18 TOTAL, the third segment of code was determined to be 5 letters long.

CAEEBXXXXXFEAADDAD

Albion Morse

The 9 crates at the base of the radio tower on Albion

The switch beneath the Albion skull does not necessarily do anything by itself; in order to hear the Morse code required to complete the Easter egg, another step is required.

At the base of the radio tower near Control Point D, there are 9 metal cases which are interactable. The Morse code is audible after performing the following steps:

Interact with each of the nine cases once
Interact with the switch underneath the Albion skull once
Interact with each of the nine cases once
Interact with the switch underneath the Albion skull four times

After performing these steps, going prone at the base of the radio tower will yield 5 letters of unique Morse code, which fill in the gap of the code that was previously determined:

CAEEB <5 letters of unique morse> FEAADDAD

Using the Code

Inside of the Sworbe lighthouse, there are 6 switches. Each switch is initially not interactable, but the switches can be made interactable by destroying lanterns in nearby houses, as shown in this map (credit to Sir-Pint-a-lot):

(Note: Destroying any of the light bulbs inside the house marked with green will stop lighthouse switches from being enabled. Be careful!)

The Morse found at the beginning of this hinted that the switches need to be numbered from TOP TO BOTTOM. The top-most switch of the lighthouse is A and the bottom-most switch is F. The code CAEEB <5 letters of unique morse> FEAADDAD can now be entered.

After inputting the code, the switches in the lighthouse will cease to be interactable. A glowing cylinder at the top of the lighthouse becomes interactable for one minute afterwards - interacting with it yields the An Escalation skin for two variants of the M1917 MG. (Note: if you fail to interact with the cylinder in time, the code will need to be entered again.)

An Escalation

The An Escalation skin for the M1917 MG (image credit to BFEE)

The An Escalation skin has a number of distinguishing features. First, it is adorned with the skulls that have been prevalent all throughout the Battlefield 1 ARG, and have been present on the A Beginning and A Conflict dogtags. The number 0627 is also visible on the skin. Finally, some Morse code is visible on the skin, which translates to UNKNOWABLE.

Turning Tides North Sea Update

On January 30, 2018, the Turning Tides North Sea update was released.

Morse Messages

When using the Infiltrator kit and standing in a few specific spots on different maps, Morse code can be heard:

Zeebrugge - inside the cabin on Control Point E: I5.D2.E7.S9.M9. EAGLE IS DOWN. GO THERE AND RETRIEVE SENSITIVE MATERIAL. (video)
Achi Baba - at the crashed plane: T0.L7.U3.N6.K8. MEET AT KANLI 6 LANDING. (video)
Cape Helles - at one of the boats: O2.P0.B5.R4.G8. MOLE SEVERED. LOST CONTACT WITH SISTER SUB. (video)
Heligoland Bight - near the beached submarine at Control Point F: Z4.X6.C1.A3.F1. SABOTAGED AT LAUNCH. INVESTIGATE APPLE OVERLOOK. (video)
Zeebrugge - at the top of the water tower near Control Point A: (video)

The Morse code in the final message is unique for each player, but takes the form of the following Latin quote with 8 letters missing:

DULCE ET DECORUM EST PRO PATRIA MORI

Letters to Numbers

The number / letter combinations that preceded each message provide a key that is used to convert the eight missing letters into numbers:

A = 3   F = 1   M = 9   S = 9
B = 5   G = 8   N = 6   T = 0
C = 1   I = 5   O = 2   U = 3
D = 2   K = 8   P = 0   X = 6
E = 7   L = 7   R = 4   Z = 4

These numbers will be input into the generator rooms on Zeebrugge (near Control Points C and D). This is accomplished by using Morse code. A dot denotes a switch in the on position, while a dash denotes a switch in the off position.

0 = -----
1 = .----
2 = ..---
3 = ...--
4 = ....-
5 = .....
6 = -....
7 = --...
8 = ---..
9 = ----.

The first four numbers are entered in this fashion in the generator room labeled 1, near Control Point C. The second four numbers are entered in the generator room labeled 3, near Control Point D. In both rooms, the numbers are entered from left to right when the generators are in front of the player. A full map is below (credit to MrHated):

Upon putting the switches into the correct position, the An Omen dogtag is unlocked.

An Omen

The An Omen dogtag

The An Omen dogtag is a gold variant of the A Beginning and A Conflict dogtags, but with the skull image slightly askew. The dogtag has the following description:

You're making a huge mistake.

June Update

On June 27, 2018, the the final stage of the Easter Egg was released.

River Somme

There is a half buried generator between B and E flags. Using limpet charges to dig it out reveals 5 interactable buttons as well as one switch to confirm the input. The generator behaves similar to the ones from Zeebrugge, a dot being on and a dash off. Using these switches to enter 0627, which is found on the An Escalation skin, will trigger a light to flash morse reading:

ATTIC SWITCH FOR WELLINGTON CHANNEL - ESCALATING DEATH COUNT - REPORT HEADSHOTS BY GROUP MOST TO FEWEST - OPEN AND CLOSE WITH NONE

Using this hint, heading to the farm house on the south-western edge of the map and blowing up its chimney will reveal a switch that once pressed will trigger the next stage of the Easter Egg. After it has been pressed, the lights on the generator from the first step become interactable once again. Using them to enter 03222110, confirming each number with the top switch, will trigger a monster howl and unlock the Angel Sighting dog tag.

Carporetto

Using the description of the Angel Sighting dog tag as a guide will unlock the Belly of the Beast dog tag. Heading to the angel statues on Carporetto, shooting off the head of the left statue, the wing of the right statue, the torso of the center statue and completely destroying the angel statue in front of them, will trigger a screaming sound and unlock a button on the base of the statue in the back. Pressing the button will unlock the dog tag.

Passchendale

To continue further, ALL five Easter Egg dog tags as well as the An escalation skin have to be unlocked!

Following the instructions of the Belly of the Beast dog tag, heading over to a caved in entrance underneath a wooden bridge near the E flag on Passchendale will reveal the path to the conclusion of the Easter Egg. Destroying the "Munitionslager" sign above the entrance will make two switches behind it interactable. Entering Unknowable in morse, where the left switch is dot and the right switch dash, will make the entrance blow up and unlock a new path. Going down the path and pressing the switch at the end of it will make the player fall down a trapdoor into a cave system. Using the scribbles found on Fort Vaux, using the compass to navigate the tunnels in the following order

W E S W E W W N S W N W S W S

will make the player drop down to the final room where he will find the Peacekeeper revolver as well as a few wooden boards spelling out Simps. This might be a reference to Kevin Simpson from the Battlefield 4 Phantom Program. G Gaining 100 kills with the Peacekeeper will also unlock the An Awakening service dog tag.

Accuracy	Spot checked
Depth	Basic
Readability	Acceptable