Co-Op Mode

Co-Op Mode is unlocked after reaching Adventure Rank 16 and completing . In Co-Op Mode, a Party of up to four Travelers can adventure simultaneously to take on Domains, participate in certain Events, and explore the open world of Teyvat together.
Cross-play between the PC, Mobile (iOS and Android), Xbox Network and PSN platforms is possible as long as the players are on the same regional server (NA, EU, Asia, or SAR).
==Co-Op Mode Menu==
The Co-Op Mode Menu lists currently online players and allows searching by UID. The list displays the player's avatar, name, Adventure Rank, profile signature, the number of people in their world, and their status.
Players can set their World Permissions to Reject Join Requests, Allow Direct Join, and Join After Approval.
The Co-Op Mode Menu can be accessed from the icon, the Paimon Menu, or the Shortcut Wheel.
==Rules and Restrictions==
;Restrictions for starting Co-Op Mode
* Players can only join worlds of players whose World Level and Adventure Rank ("AR") range is lower than or equal to their own.
** In the case of the Serenitea Pot, players can join their Friends' Serenitea Pot regardless of either one's World Level or AR.
** Players with World Level 8 and 9 can freely enter each other's worlds.
* Certain Archon Quests, Story Quests, World Quests, and Event Quests may manipulate the world and hence disable access to Co-Op Mode, even if the quest is not the active quest. This will also disable the player's access to their own Serenitea Pot. Some quests may temporarily re-enable Co-Op Mode between steps.
** If a quest is currently manipulating a host and the host has just completed the activity, it will take some time before the host can be joined. The host can log out and back in to speed up the process.
** While Co-Op Mode is disabled, any activity that requires entering the Co-Op screen — even if it can be played solo — cannot be started until Co-Op Mode is reactivated.
*** Examples include the Fading Star challenge during Unreconciled Stars and Frostborn Miracle during The Chalk Prince and the Dragon.
;Rules during Co-Op Mode
* If two players Co-Op together, each of them can choose two characters for the party and swap between them in combat like they can in solo. If three players Co-Op together, the host gets two characters while the others get one. With four players in Co-Op, each player gets one character to use in battle.
** Players can change their fielded character(s) through the Party Setup menu while not in combat.
** It is possible for players to have the same character when outside of Domains, but not in Domains.
* Enemies and enemy variation types scale with the number of players currently in the world.
While not a game rule, it is generally considered impolite to take time-gated resources; such as certain ores, fishes, plants or other wildlife; without the host's permission. Some players refer to this as stealing.
==Activities==
===Co-Op Activities===
;Activities that players can carry out in Co-Op
* Domains and Ley Line Outcrops (although they must be initiated by the host).
** When entering Domains (dungeons), characters within the party must be unique. Although they usually count as the same character, both the male and female Traveler can be present at once.
** After completing Ley Line Outcrops, Domains, or boss challenges, each player may choose to revitalize the Petrified Tree or Ley Line Blossom by using Original Resin to receive individual rewards.
* Commissions
** A player can only receive rewards for up to 4 commissions, regardless of whether the commissions were completed solo in their own world or in Co-Op with other players.
** Certain commissions cannot be progressed while in Co-Op Mode. See page for more information.
* Co-Op Events
* Some World Quests, excluding Adventure Rank Ascension quests.
* Hunting and defeating monsters and bosses in the open world. (Note some boss fights can only be initiated by the host.)
** This excludes the Stormterror domain.
** This includes defeating the Unusual Hilichurl.
* Collecting Resources.
** Some resources can be collected by all players in a Co-Op session, such as ore (excluding Cor Lapis) and dropped loot from Common Enemies and Elite Enemies.
** Plants found in the open world cannot be collected by multiple players in the same session i.e., can only be collected once and by one person.
** Wood can be gathered from the same trees, although wood only drops for whoever hits the tree.
* Fishing.
* Weekly Bounties, but only the host can access and gain Reputation.
* Cooking.
* Switching characters.
* Healing at the Statue of The Seven.
* Resonating with the Statue of The Seven for the Traveler to change element.
* Earning Achievements.
* Viewing your individual map pins.
* Completing Open World mechanism-activated Time Trial Challenges, which must be started by the host.
* Making use of Elemental Resonance even with characters from another party (e.g., if Player 1 has a Pyro character in their party and Player 2 has a Pyro character in their party, both players will have the Fervent Flame attack buff active).
* Some Character Talents will affect Co-Op partners' characters. These include:
** The Healing abilities of characters, including but not limited to Barbara, Bennett, Diona and Jean.
*** This excludes self-healing abilities such as Hu Tao's Spirit Soother and Fischl's Her Pilgrimage of Bleak.
** The Co-Op shields generated by Diona's Shaken, Not Purred (C2) and Zhongli's Stone, the Cradle of Jade (C2).
;Activities that can only be carried out in Co-Op
* Co-Op-related Achievements (see #Achievements)
** Boss-related Co-Op achievements will not be obtained if only one player fights the boss, even if done in Co-Op Mode.
** The achievement Temari for Life, which requires hosting a game of Temari.
** The achievement "Call Me Ishmael.", which requires catching a fish in another player's world.
** The achievement Nice Boat! which requires switching Waveriders with another player.
* Certain events, like Rhodeia's Rage and The Chalk Prince and the Dragon's Resurgent Cryo Regisvine, require entering "Special Event Mode," which automatically switches the world to Co-Op. This will not match you with other players, but by having "Allow Direct Join" enabled, some players will be able to join and play along with you.
===Restricted Activities===
;Activities that players cannot carry out in Co-Op, except for the Host
* Activate elemental monuments.
* Open Chests or pick up Sigils.
* Interact with Investigation points.
* Pick up Oculi.
* Use a Treasure Compass.
* Initiate events, such as encountering a Seelie, spawning Oceanid, or unlocking domain doors.
* Spiral Abyss.
* Adjust the time of day.
* Make offerings to the Statue of The Seven or set the amount to be healed, however you can be healed or change your Traveler's element.
* Enter the Host's Serenitea Pot (must be a friend to do so).
;Activities that players cannot carry out in Co-Op, not even as a Host
* Talk to or interact with a majority of NPCs, including Katheryne and Shop owners, activating a new Statue of The Seven, and activating a Dendro Slime ambush.
* Have the game paused while on the menu screen, even in a Co-Op room where you're the only player.
* Certain events, such as Contending Tides, can only be completed in single-player mode.
* Story Quests, which are temporarily paused. They can be continued once Travelers leave Co-Op Mode. If the Host is currently in a Story Quest, Co-Op Mode will be disabled until the quest is completed or cancelled.
* Gain the other player party character's passive abilities (for example, Razor's sprint stamina passive, Ningguang's mining outcrop spotting passive, and Tartaglia's Master of Weaponry will not apply for the other player).
** This also applies to constellations, including Rite of Resurrection and Dedicating Everything to You.
==Co-Op Scaling==
Players	Enemy Base HP	Enemy Base ATK
1 	100% 	100%
2 	150% 	110%
3 	200% 	125%
4 	250% 	140%
* This table displays how enemy health and damage dealt to players scale up in Co-Op Mode.Reddit: Analysis thread by u/Saber1202
* Overworld stats will scale based on the number of players in the session, even if some are in a Domain.
* Domain stats on the other hand will scale based on the number of players in the Domain only.
* Damage from Ley Line Disorders and Auras does not scale up with players.
* Companionship EXP rewards are doubled in Co-Op Mode with two or more players.
==Achievements==
==Change History==
==References==
==Navigation==
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