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
Clarity IClarity ISupport, Buff, Persistent Category: Clarity Tier: 1 Additional Reservation: 10 SpiritSupport Requirements: +5 IntSupports PersistentBuff Skills, causing you to gain increased Mana Regeneration while the Skill is active.30% Increased Mana Regeneration Rate while a Supported Skill is activePlace 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.
Vitality IVitality ISupport, Buff, Persistent Category: Vitality Tier: 1 Additional Reservation: 20 SpiritSupport Requirements: +5 StrSupports PersistentBuff Skills, causing you to gain Life Regeneration while the Skill is active.Regenerate 1% of maximum Life per second while a Supported Skill is activePlace 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
Boundless Energy IBoundless Energy ISupport Category: Boundless Energy Tier: 2 Cost & Reservation Multiplier: 115%Support Requirements: +5 IntSupports Meta Skills. Supported Skills generate Energy significantly faster.Supported Skills gain 35% increased EnergyPlace 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.
Mysticism IMysticism ISupport, Buff, Persistent Category: Mysticism Tier: 2 Additional Reservation: 15 SpiritSupport Requirements: +5 IntSupports PersistentBuff Skills, causing you to deal increased Spell Damage while on full Energy Shield while the Supported Skill is active.Deal 30% increased Spell Damage while on full Energy Shield while a Supported Skill is activePlace 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
Energy RetentionEnergy RetentionSupport, Trigger Category: Energy Retention Tier: 3 Cost & Reservation Multiplier: 110%Support Requirements: +5 IntSupports Meta Skills. Supported Skills gain a chance to partially Refund a portion of Energy cost when Triggering or Invoking other Skills.Skills Triggered by Supported Meta Skills have 35% chance to refund half of their Energy 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.
FlukeFlukeSupport, Trigger Category: Fluke Tier: 3 Cost & Reservation Multiplier: 120%Support Requirements: +5 IntSupports Skills which Trigger other Skills. Skills Triggered by Supported Skills have their Damage randomly raised or lowered when Triggered, as well as recovering a random amount of their cost when Triggered.Skills Triggered by Supported Skills deal between 40% less and 60% more Damage Skills Triggered by Supported Skills recover between 0% and 20% of cost on usePlace 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
Boundless Energy IIBoundless Energy IISupport Category: Boundless Energy Tier: 4 Cost & Reservation Multiplier: 115%Support Requirements: +5 IntSupports Meta Skills. Supported Skills generate Energy significantly faster.Supported Skills gain 45% increased EnergyPlace 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.
Clarity IIClarity IISupport, Buff, Persistent Category: Clarity Tier: 4 Additional Reservation: 20 SpiritSupport Requirements: +5 IntSupports PersistentBuff Skills, causing you to gain increased Mana Regeneration while the Skill is active.50% Increased Mana Regeneration Rate while a Supported Skill is activePlace 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
Cold MasteryCold MasterySupport, Cold Category: Mastery Tier: 5Support Requirements: +5 IntSupports Cold skills, granting them an additional level. Does not support skills which do not have levels.+1 to Level of Supported Cold 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.
Lightning MasteryLightning MasterySupport, Lightning Category: Mastery Tier: 5Support Requirements: +5 IntSupports Lightning skills, granting them an additional level. Does not support skills which do not have levels.+1 to Level of Supported Lightning 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.
Item acquisition
Cast on Elemental Ailment has restrictions on where or how it can drop.