Party

Parties are a core gameplay mechanic in Granblue Fantasy. A party consists of 1 to 6 characters, a set of 0 to 10 weapons and a set of 1 to 5 summons.

Characters

Main Article: Character

Each party uses 3 main members and 2 sub members. In a quest, your main character and your 3 main members will immediately enter battle, based on the order that they are present in character slots. Only 4 members may be in battle at a time.

Sub members enter battle, in order, as main members leave. This can happen as characters get defeated, or through certain skills such as  ChangeMain Character switches positions with a sub ally., or even through some bosses' special attacks.

Sub members normally have no effect on the party until they become main members, but a few have effects that take place even when a sub ally, or sometimes only while they are a sub ally, for example Sevastien's  Grandbutler Knows BestWhen Sub Ally: Refresh 3% of all allies' HP at the end of a turn (Healing cap: 150). or Lily's  Shine Crystal10% boost to DEF.
At level 95:
Boost to DEF now applies to all allies.
Fire damage reduction to Water allies based on their number of Deluge CrestWater magic is amplified (Max: 5 / Can't be removed)
.
(Fire DMG reduction takes effect even when Lily is a sub ally.).

Weapons

Main Article: Weapons

Each party uses 1 main weapon and up to 9 sub weapons. This is colloquially known as the "weapon grid", or "grid" for short. The main weapon of the grid dictates the element and charge attack of your main character. Each weapon can have up to three modifiers known as Weapon Skills. All weapons in your grid are always active (with rare exceptions such as certain characters' fate episodes) and apply to all characters in your party unless the skill is otherwise restricted. A very common restriction is "[element] allies", such as "fire allies", but there are more complex restrictions or conditions around.

The HP and ATK values of all equipped weapons apply directly to all characters in your party, and are enhanced by the skills in the grid. If you do not have a main weapon equipped, your main weapon will automatically become an extremely weak class-specific weapon in battle.

Summons

Main Article: Summons

Each party uses 1 main summon and up to 4 sub summons. This is also known as the "summon grid". Aura effects from summons only apply when used as a main summon or support summon. The HP and ATK values of all equipped summons (excluding support summons) apply directly to all characters in your party, and are also enhanced by the skills in the grid.

Some summons, such as Arcarum Summons, also have a separate aura that only takes effect when they are not a main (or support) summon — this is the sub aura effect. Once the player reaches Rank 100, two extra slots used only for sub aura effects become available to all parties, and only allow equipping summons with a sub aura effect. These extra 2 summons give no ATK or HP, and cannot be called; they strictly contribute only their sub aura effect.

Name

Parties can be renamed by the player by clicking the pencil icon on the party screen. The name is visible only to the player, and only when switching parties inside the party editor, it is not visible in the smaller party selector used when choosing your support summon.

Party names are limited to 6 characters total, and this cannot be bypassed. There is no obvious way to return the party name to default, but this can be accomplished by naming the party 0 and reloading the page.