Online:Grouping

thumb|right|Grouping Tools (PC; Dungeon Tab)
Grouping with other players is an important aspect of Elder Scrolls Online, and is often necessary to complete group content. Unlike player guilds or friends, groups are temporary, character-bound, and (in PvP zones) Alliance-restricted. Grouping provides a 10% Experience bonus to everyone in the group. Each group has a leader, identified by a crown icon. Fellow group members can be identified by an arrow icon. Groups come in two sizes:
Regular Groups consist of up to 4 players, and are needed to complete Group Dungeons, Dragonstar Arena, and Blackrose Prison.
Large Groups (informally known as "raids") can hold up to 12 players, and are primarily used for Trials and AvA battles in Cyrodiil
Once a group leader reaches Level 50 and unlocks Veteran content, the option to switch the group between Normal and Veteran mode becomes available. This option determines which version of a Group Dungeon (or Dragonstar Arena, Blackrose Prison, and Maelstrom Arena) the group enters. Group Dungeons also scale to the level of the group leader. The number of players in a group dictates the amount of experience received. A group of two actually receives bonus experience compared to solo play , but the returns decrease as more players join.
 

Group and Activity Finder
The Group & Activity Finder replaced the Grouping Tools in Update 9. The Role selection between Tank, Healer and Damage is now required, and is designed to create balanced groups for certain activities. It is no longer possible to passively search for groups for World, Alliance War and Trial activities, and the group search for Dungeons has been moved into the Dungeon Finder tab.

In addition to the Dungeon Finder, the Activity Finder also includes sections for Group settings, Endeavors, the Zone Guide, and access to Battlegrounds.

Dungeon Finder
The Dungeon Finder is a special grouping tool for running Group Dungeons, sometimes referred to as "pick-up groups" (PUGs).
One member will randomly designated as the group leader. This is purely cosmetic as this member has no more privilege than any other group member, e.g., they cannot kick out a group member. 
Kicking out a member is done by voting amongst the other members
When members leave the group, they are automatically removed from the instance and are sent back to where they came from, after a 2 minute delay to allow players to end quests and gather rewards.

Filling an Established Group
If you already formed a group using the Dungeon Finder but are short one or two members, you can add your group to the Group & Activity Finder and it will fill the missing slots. In this case:
The group leader does not change. 
Kicking a member still requires a vote unless that member was in the original group.

Notes
Prior to Update 8, a single Grouping Tools tab allowed players to passively look for a group to join for a variety of different activities, including World, Alliance War, Dungeon, Veteran Dungeon and Trial. To join a group, you could select one or more preferred roles from Tank, Healer, or Damage. Group searches could be specified by listing which roles you're looking for, what size group you wish to join, and optionally the specific location of the activity. For World activities, use of the group finder was limited by level, and Alliance Zones were divided by subzone.
The ability to search for an Alliance War group using the Activity Finder was removed in Update 25 due to lack of use.
Groups were originally split into Regular (4 players), Medium (12 players), and Large (24 players). Large Groups were primarily used for AvA battles in Cyrodiil, but could be formed in PvE zones as well. The ability to add more than 12 players to a group was removed in Update 30.

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