Rage is an offensive Buff in Path of Exile 2.

Rage is an offensive Buff in Path of Exile 2.

Rage is a stacking Buff that grants more Attack Damage. Each stack of Rage provides '1% more Attack Damage', up to a default maximum of 30 Rage for '30% more Attack Damage'. You lose Rage over time if you haven't taken Damage or gained Rage in the last 2 seconds.
Tip: whilst many of the sources of Rage generation are inherently tied to Melee mechanics such as Melee Support Gems or Melee Skills, note that the Rage Buff itself grants a generic more multiplier to all Attack Damage, including non-Melee Attacks such as any Projectile Attacks. Rage is therefore a valuable, flexible Buff that can be fit into any Attack-based build as long as you're able to generate and sustain it.
There are many ways to generate Rage, but the most common sources are modifiers that grant 'Gain X Rage on Melee Hit'. These modifiers are summed together to provide a total amount of Rage gained per Melee Hit, and Rage gained this way cannot occur more than once per 0.5 seconds.
Other methods of gaining Rage include, but are not limited to, using a Warcry supported by Raging Cry or Leeching Rage via the Damage dealt by a Totem linked to Font of Rage.
Note: non-Hit sources of Rage generation are not limited by the same timer.
Rage is technically a temporary Buff, but it does not have a fixed Duration. Instead, Rage has an inherent Rage Loss mechanic that makes you lose Rage over time if you haven't gained any Rage or taken any Damage for a short period of time.
You lose 1 stack of Rage every 0.1 seconds if you haven't taken Damage or gained Rage in the last 2 seconds. By default you'll therefore lose 10 Rage per second when losing Rage this way. However you can invest into modifiers to slow the Rate of Rage Loss or extend the Rage Loss timer. For example
Prolonged Fury will make Rage decay slower if it has already started, whilst the small nodes leading to
Unforgiving grant the modifier 'Inherent Rage Loss starts 1 second later', providing a longer window before Rage Loss begins.
The
Death Articulated Unique Gloves grant the special modifier 'No Inherent loss of Rage', fully preventing the Rage Loss mechanic.
Blood of the Warrior will also prevent the inherent loss of Rage during its Flask effect.
The default maximum Rage is 30 stacks. You can invest into modifiers to maximum Rage to improve this maximum, such as
Battle Trance.
The bonus gained from Rage can be added to by utilising modifiers with very specific wording. These modifiers must read 'Every Rage also grants X' to provide their additional bonuses that scale based on the total amount of Rage, but also scale with Rage Effect.
For example
Vengeful Fury will make each stack of Rage also grant 1% increased Armour. Any time a modifier is worded like this, it will also be scaled by any modifiers that improve the Effect of Rage, see below for more information.
You can improve the Effect of Rage with modifiers such as the one on the
Berserk Persistent Buff Skill. These modifiers multiply the total effect of all modifiers granted by the Rage Buff.
For example, a Level 20
Berserk grants 59% increased Rage Effect. If you had 30 Rage and also had
Vengeful Fury allocated, you'd be gaining '47% more Attack Damage' and '47% increased Armour' after
Berserk's Rage Effect has scaled the Buff (30 * 1.59).
Ngamahu's Chosen is a Charm that will cause you to gain up to your maximum Rage limit upon use.
The
Hateforge Unique Gloves will cause you to lose all of your Rage upon reaching maximum Rage, but will also grant 1-3 random Charges in return.