Destiny 2 “Episode: Heresy” Chess Puzzle Event Guide

The Destiny 2 “Episode: Heresy” Chess Puzzle Event was far more than just a simple in-game activity involving chess mechanics. It was meticulously designed by Bungie as a comprehensive, multi-part Alternate Reality Game (ARG) specifically intended for the Destiny 2 community to solve collaboratively. Its significance lies in its purpose: it wasn’t just for rewards, but was a carefully crafted mystery designed to be tackled by players globally ahead of the major Edge of Fate expansion reveal scheduled for May 2025. It integrated in-game challenges with out-of-game investigation and data collection, serving as both a narrative experience tied into the lore of Episode: Heresy and a community-wide challenge.

To embark on this mysterious event, your journey begins in a specific and rather private location within the game world: Eris Morn’s apartment in the Last City. You can access this personal instance by simply selecting the Last City destination node on your game map. Unlike public social spaces, this is a unique instance you load into, where the secrets related to the chess puzzle are hidden away.

Yes, there is one critical prerequisite mentioned in the guide. The entry point that teleports you into the actual puzzle dimension is described as a “spooky interdimensional slit” located near the back of Eris Morn’s apartment. This particular access point is restricted and will only become interactable and accessible to players who have completed the main story campaign of Destiny 2. Therefore, finishing the core narrative is a necessary step before you can even discover the location of the interactive chess set.

Having successfully entered Eris’s private space within the Last City and completed the main story campaign, you need to visually locate the newly added interactive element: a chess set placed on a table. The guide indicates its position is found by dropping down beneath Eris’s “creative space.” Once you find this chess set, approach it and interact with the prompt that appears. The guide specifically mentions interacting with the option to “Pick up the king.” Selecting this interaction on the chess set will instantaneously transition you out of Eris’s apartment and transport you directly into the mysterious dimension known as the Unknown Antechamber activity, which is where the puzzle-solving takes place.

Indeed, there is a significant gating prerequisite for what the guide calls the “Middlegame” phase, which encompasses the core 27 chess puzzles. To unlock these challenges, your character must first collect 60 specific “Chess Piece” collectibles. These pieces were initially part of a community-wide scavenger hunt and are scattered across various locations within Destiny 2, including Eris’s flat, the Tower, the EDZ, Europa, and the Nether areas introduced during Episode: Heresy. While the intense race to find these is over, you still need to personally collect all 60 on your character’s profile to access the puzzles normally.

Fortunately, the guide offers an alternative method if you haven’t completed the collection of all 60 Chess Pieces yourself. You can bypass this individual requirement by simply joining a fireteam with another player who has successfully collected all 60 pieces on their character. Being in a fireteam with someone who meets this prerequisite allows you, even if your own collection is incomplete, to interact with the chessboard in Eris’s apartment and enter the Unknown Antechamber activity directly into the “Middlegame” mode alongside them.

The “Middlegame” is identified as the initial primary puzzle phase within the Unknown Antechamber, which becomes accessible after fulfilling the 60-piece collection requirement or joining a qualifying fireteam. This phase focuses entirely on solving a sequence of 27 distinct chess puzzles. These challenges are presented directly on the giant, interactive chessboard within this mysterious dimension. Successfully completing all 27 of these specific puzzles is a key step in the event’s progression and is necessary for the completion of the hidden “En Passant” Triumph.

The giant chessboard in the Unknown Antechamber is a unique interactive environment. The board itself is clearly laid out with standard chess coordinates, marked A through H horizontally and 1 through 8 vertically, making it easy to reference squares. Around the board’s periphery are various glowing pedestals. These pedestals act as nodes representing the different white chess pieces you can utilize (Rook, Knight, Pawn, Queen, Bishop) as well as special actions like “Take” and “Delete.” To interact, you stand on the pedestal corresponding to the piece or action you want to perform. Then, you aim your character’s view and “shoot” the specific coordinate square on the giant board where you want to place the piece or apply the action. The objective for each of the 27 puzzles is fundamentally a “checkmate-in-one” scenario: you must strategically place or use white pieces such that White will deliver a checkmate to Black on their very next theoretical move, while simultaneously ensuring that your own King piece is not put into check by Black’s current setup or your actions.

In addition to placing pieces, the giant chessboard provides pedestals for special manipulations. The “Deletion” pedestal allows you to remove any piece currently on the board, white or black. To use this, you simply stand on the Deletion pedestal and accurately shoot the square occupied by the piece you wish to remove. This can be helpful for clearing space or correcting misplacements. The “Take” pedestal operates differently than a standard capture. Instead of just removing an enemy piece, standing on the Take pedestal and shooting a square occupied by a black enemy piece will convert that piece into an allied white piece under your control. This action is crucial in some puzzles, turning enemy threats into friendly assets.

The event is designed to allow for experimentation and correction. The guide highlights two useful tools on the giant chessboard. There is a specific book pedestal available; interacting with this pedestal will fully reset the current puzzle back to its original starting arrangement, allowing you to completely restart if you find yourself in an unsolvable state or want to try a different approach from the beginning. Furthermore, there is a glowing green button pedestal which functions as an undo mechanic. Interacting with this green button will revert only your single most recent action, providing a quick way to correct small errors without having to restart the entire puzzle. The guide encourages players to enjoy the process and not fear making mistakes, suggesting these tools make experimentation feasible. It also recommends using a precision weapon, like a Scout Rifle, to ensure you accurately hit the intended square when aiming from the pedestals.

When you correctly solve one of the 27 Middlegame chess puzzles, the game provides clear confirmation. You will see a distinctive success banner pop up on your screen, often displaying messages like “Absolute Pin.” Yes, the guide confirms that you can earn rewards before completing the entire set of 27 puzzles. By reaching certain milestones or completion points within the sequence of challenges, you will be rewarded with Episode: Heresy weapons. The guide also specifically notes that Adept versions of these weapons become available at designated points as you progress through and solve more of the puzzles, serving as progressive rewards for your efforts.

Completing the entire sequence of 27 Middlegame chess challenges signifies the conclusion of the first major puzzle phase. Upon solving the final puzzle, the Unknown Antechamber activity undergoes a transition. The guide states that the space “shifts” into “Endgame” mode. This transition unlocks new interactive elements and functionalities within the same activity space, specifically setting the stage for the collaborative community-based puzzle phase of the event.

Once you reach Endgame mode, a notable change occurs on the side of the giant chessboard: the “Take” pillar transforms into a glowing, water-filled font or basin. This font is a critical interactive point for the next stage. Interacting with this basin allows you to “peer into” a unique vision. The game will display a specific, randomly assigned chessboard arrangement featuring pieces. These pieces will then visually fade, leaving only their symbolic representations drawn on the squares. Simultaneously, a unique four-digit code, labeled “Signal,” will appear as a temporary buff on the left side of your screen (e.g., x1298, 404). This unique vision and accompanying code signal the beginning of the community-driven phase, where each player contributes individual pieces of data (their unique board pattern and code) that must be shared and compiled globally.

The A.I.O.N. Archives, which stands for Apollo Intertemporal Observation Network, is a secret ARG website created by Bungie specifically for this event. It was designed as a retro-style web console terminal, adding a layer of mystery and technical investigation. The community’s discovery of this site was a testament to their collaborative power. By diligently gathering and sharing the many different unique chessboard patterns players saw in their watery font visions from the in-game Endgame activity, they realized these individual images could be stitched together. This collective effort formed a large mosaic that, upon completion, was discovered to be a scannable QR code. Scanning this QR code using a phone or other device led players directly to the hidden A.I.O.N. Archives website, bridging the gap between the in-game puzzles and the external ARG component.

The A.I.O.N. Archives website served as a vital tool for processing the data collected in-game and advancing the mystery. Players could interact with the console using text commands. Typing in specific three-digit numbers (like 001 through 0203) often revealed snippets of lore pages and cryptic messages, providing narrative context potentially hinting at future events. The core puzzle interaction involved using the command 11104 to access an “experimental database mode.” After entering 11104, the console would prompt the player first for the four-digit “Signal” code they received from the watery font in-game. It would then ask for an “Experiment Code,” which was the specific chessboard layout from their vision, encoded in the standard chess FEN (Forsyth-Edwards Notation) format. The console would process this unique combination of signal code and FEN string, yielding various intriguing text outputs such as ‘Compressed data’, ‘quantum spin fail’, or ‘data found’. Because each player had a unique signal code and FEN, the community had to work together extensively, sharing their individual data and console outputs in community hubs, to collectively analyze the results and understand the puzzle’s structure.

FEN stands for Forsyth-Edwards Notation. It’s a widely recognized standard system for describing the current state of a chess game on a board using a single line of text characters. To obtain the specific FEN code needed for the A.I.O.N. Archives (when prompted for the ‘experiment code’ after using the 11104 command), players had to accurately recreate the unique chessboard pattern they saw displayed during their vision from the watery font in the in-game Endgame activity. The standard method for doing this was to use an online FEN viewer tool. Players would visit such a website and manually set up the chessboard on the tool’s interface, placing the white and black pieces exactly as they appeared in their in-game vision. The online tool would then automatically generate the corresponding FEN string for that specific board setup. Players would copy this generated FEN string and paste it into the A.I.O.N. console. The guide emphasizes the importance of copying only the core FEN string and avoiding any extra information the online viewer might automatically add, like turn numbers or castling rights, to ensure the console accepts the input correctly.

Yes, a notable hidden reward was indeed discovered directly as a result of the community’s extensive interaction and data submission to the A.I.O.N. Archives website. During the systematic process of inputting thousands of unique signal codes and their corresponding FENs into the console, one particular combination yielded an output that included a Bungie redemption code. This code was for the “Secret Signal” emblem. The guide provides the specific code, JGN-PX4-DFN, and confirms that this code can be redeemed by any player on Bungie’s official code redemption website. This served as concrete proof that engaging with the external web-based ARG component of the puzzle could yield real, in-game cosmetic rewards.

The Endgame phase was characterized by intense, round-the-clock collaboration among dedicated community members. As the guide highlights, over a period of roughly 36 hours (April 30 to May 1, 2025), players tirelessly collected, shared, and decoded all the data submitted to the A.I.O.N. Archives. This massive, collective data analysis effort allowed them to piece together the overarching puzzle and derive a single, definitive “final answer” – which took the form of a specific, complex arrangement of chess pieces that needed to be placed on the in-game board. This final layout was quite intricate, notably involving specific counts of pieces like seven Queens, seven Rooks, seven Bishops, seven Knights, and seven Pawns positioned on particular squares. Once the community was confident they had determined the correct final configuration from the ARG data, groups of players in-game returned to the Unknown Antechamber while in Endgame mode. There, a new interactive prompt appeared at the book console (which previously served as a reset tool): “Offer Your Answer.” By interacting with this prompt and then carefully using the piece pedestals and board coordinates to recreate the collectively determined final board layout on the giant chessboard, players successfully submitted the ultimate solution to the entire ARG.

Successfully submitting the correct final board layout in the Unknown Antechamber triggers the climactic payoff for completing the entire event. The guide describes this moment: all the braziers positioned around the giant chessboard ignite simultaneously, a triumphant message appears on screen, and the watery font glows intensely with a new prompt, “The water reveals all…”. Interacting with this glowing font activates a special, secret cinematic cutscene. This scene reveals significant new lore regarding the Nine and their Apollo Intertemporal Observation Network (A.I.O.N.), clearly connecting the event’s mystery to upcoming developments in Destiny’s narrative, particularly the next chapter. After the cutscene concludes, a special reward chest called “Riches of the Clever” materializes. Opening this chest grants a significant haul of exclusive collectibles and highly valuable in-game materials, including the unique Umbral Rumble shader, the exotic Deinterlace ship, the exclusive Enigmatology emblem, high-tier resources like Ascendant Shards and Strange Coins, an Exotic Cipher, and various “Curio of the Nine” items which are likely lore collectibles. Furthermore, the “En Passant” triumph is fully completed for players who finish this phase, and a new lore book detailing the Drifter’s experiences during Episode: Heresy is unlocked for lore enthusiasts to read.

Yes, absolutely. The guide explicitly confirms the current status of the event: although the community-driven ARG portion has been fully solved and narratively concluded, the core in-game chessboard activity within the Unknown Antechamber remains playable in Destiny 2, at least at the time the guide was written. This is excellent news for players who missed the initial live solve. It means new or returning Guardians can still participate from the beginning, completing all the steps at their own pace. This involves potentially collecting the 60 pieces (if needed), solving all 27 Middlegame puzzles, unlocking the Endgame mode, learning about the historical role of the A.I.O.N. Archives, and critically, they can then offer the final collective solution that the community already determined (as detailed in guides like yours). By doing so, they can still witness the finale cutscene and claim all the exclusive rewards, including the Adept weapons earned during the Middlegame and the full contents of the Riches of the Clever chest from the Endgame. The guide speculates that Bungie is likely to leave this activity accessible throughout the remainder of Episode: Heresy or possibly even for the entirety of the current year, mirroring how past secret missions have remained available.