The following support gems are recommendations by GGG as listed in-game, and do not necessarily reflect optimal combinations or the views of the wiki.
Gem tier
Support gems
I
ExpanseExpanseSupport, AoE Category: Grants Cooldown Tier: 1 Cooldown Time: 8.00 sec Can Store 1 Use(s)Support Requirements: +5 IntSupports any Skill that you use yourself, granting it significantly higher Area of Effect but causing it to gain a long cooldown. Cannot support Skills which already have a cooldown.Supported Skills have 50% increased Area of Effect Supported Skills have a Cooldown of 8 secondsPlace into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple Support Gems of the same Category socketed within one Skill.
Prolonged Duration IProlonged Duration ISupport, Duration Category: Prolonged Duration Tier: 1 Cost & Reservation Multiplier: 120%Support Requirements: +5 StrSupports any skill that has a duration, making that duration longer.Supported Skills have 30% more Skill Effect DurationPlace into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple Support Gems of the same Category socketed within one Skill.
II
Encroaching GroundEncroaching GroundSupport, AoE Category: Encroaching Ground Tier: 2 Cost & Reservation Multiplier: 110%Support Requirements: +5 IntSupports Skills that create Ground Surfaces, causing those Surfaces to grow over time, up to a limit.Ground Surfaces created by Supported Skills gain 20% increased Area of Effect per second, up to a maximum of 100%Place into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple Support Gems of the same Category socketed within one Skill.
Persistent Ground IPersistent Ground ISupport Category: Persistent Ground Tier: 2Support Requirements: +5 StrSupports Skills which create Ground Surfaces, causing created Surfaces to last much longer.50% increased duration of Ground Surfaces created by Supported SkillsPlace into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple Support Gems of the same Category socketed within one Skill.
III
Astral ProjectionAstral ProjectionSupport Category: Astral Projection Tier: 3Support Requirements: +5 IntSupports Nova Skills, causing those Skills to take place at the targeted location when used instead of around you.Supported Skills Cast at the targeted location instead of around you Supported Skills have 25% less Area of EffectPlace into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple Support Gems of the same Category socketed within one Skill.
Persistent Ground IIPersistent Ground IISupport Category: Persistent Ground Tier: 3Support Requirements: +5 StrSupports Skills which create Ground Surfaces, causing created Surfaces to last much longer and only end when their duration expires.50% increased duration of Ground Surfaces created by Supported Skills Ground Surfaces created by Supported Skills cannot be destroyed except by expiringPlace into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple Support Gems of the same Category socketed within one Skill.
IV
Efficiency IIEfficiency IISupport Category: Efficiency Tier: 4Support Requirements: +5 StrSupports any skill, making it cost less to use. Cannot support skills which reserve Spirit.Supported Skills have 40% less CostPlace into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple Support Gems of the same Category socketed within one Skill.
Rapid Casting IIRapid Casting IISupport, Spell Category: Rapid Casting Tier: 4Support Requirements: +5 IntSupports Spells, causing them to cast faster.Supported Skills have 20% increased Cast SpeedPlace into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple Support Gems of the same Category socketed within one Skill.
V
Persistent Ground IIIPersistent Ground IIISupport Category: Persistent Ground Tier: 5Support Requirements: +5 StrSupports Skills which create Ground Surfaces, causing created Surfaces to last much longer as well as lowering the Cooldown Recovery Speed of affected Enemies. Ground Surfaces from Supported Skills only end when their duration expires.50% increased duration of Ground Surfaces created by Supported Skills Ground Surfaces from Supported Skills apply Suppressive Ground Suppressive Ground inflicts 30% less Cooldown Recovery Rate Ground Surfaces created by Supported Skills cannot be destroyed except by expiringPlace into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple Support Gems of the same Category socketed within one Skill.
Rapid Casting IIIRapid Casting IIISupport, Spell Category: Rapid Casting Tier: 5Support Requirements: +5 IntSupports Spells, causing them to cast faster for each different Spell you've cast Recently.Supported Skills have 10% increased Cast Speed for each different Spell you've Cast in the last eight secondsPlace into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple Support Gems of the same Category socketed within one Skill.