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Buffs are a type of effect that can modify a creature's statistics. Those with primarily detrimental effects are typically referred to as debuffs.
Identifying a buff
Each buff affecting the player will display an icon in the top-left of the screen. This is one way to determine whether or not an effect is a buff - if it does not show an icon, it is not a buff that is attached to the player. The exception to this is charges and elemental status effects, which also show an icon but are not buffs.
- All player aura skills(both your own as well as those received from other players)
- All positive auras from friendly monsters(Spectres from Raise Spectre ability, Dominating Blow monsters)
- Rejuvenation Totem aura
The functioning of buffs
A buff simply adds statistics and modifiers to the creature it is attached to. Although a buff may increase the damage of the that the affected creature deals with hits, a buff itself cannot deliver hits or take any action. A buff may include degeneration or damage-over-time effects. For example, if a monster is attacked by a player using theaura, the monster is not "hit" by the aura, or the buff, it is the player that hits the monster:
- Wrath is a spell that is cast by the player.
- The spell creates an aura that applies a buff to any allies within range.
- The buff contains a modifier that adds lightning damage to the player's attacks
- The player hits the monster, dealing the added lightning damage
All buffs have a duration, which can be infinite (as in the case of auras). This duration is affected by Buff Duration modifiers, and can also be affected by Skill Effect Duration modifiers if the buff was applied by a skill.
The passive skills which increase buff and debuff duration apply not to buffs on you but to buffs (including debuffs) you create, either on yourself or other entities. This includes all the above as well as such things as the debuffs placed on cursed monsters.
The effect of a buff can also be altered, buff effect modifiers alter the numerical values of the buff. For instance, the notable passive skill Inner Force grants a 15% increased Effect of Buffs on you modifier. This will increase:
- The amount of mana regeneration granted by the Clarity aura
- The amount of Fire Damage per second taken by the player using Righteous Fire
- The spell damage bonus provided by a player using Righteous Fire
It will not increase the amount of Fire Damage per second taken by monsters that are nearby a player using Righteous Fire, because Inner Force specifies it only applies to buffs "on you".
The Inner Force and Buff Effect passives increase the bonuses from buffs that affect yourself. It does not increase damage dealt from buffs as it is something that affects enemies.
Therefore one has to be careful when amplifying some two-sided effects. For instance, Righteous Fire increases the spell damage bonus from the buff, but also increases the damage dealt to yourself without increasing the damage dealt to enemies. Using Blood Rage increases the life leech amount as well as the attack speed on you, but also increases the Chaos Damage degeneration.
A debuff is simply a buff that only provides a detrimental effect to the debuffed creature. Effects must be closely examined to determine whether they are considered a buff or debuff by the game, as it is not obvious. For instance both the bonus spell damage and the self-burn damage from Righteous Fire are part of a single buff, despite the fact that the burn is a detrimental effect. Another example is, poison damage is a debuff, while burn and bleed damage are status ailments.(exception is burn damage from Fire Trap is a debuff)
Incomplete list of buffs & debuffs
Some skills create buffs, but they are not buffs themselves.
- The effects from all active aura skills
- The effects from all curses
- The armour bonus from
- The Chaos damage, attack speed, and life leech effects of
- The charge timers of
- The duration effect placed on enemies by that turns them into minions
- The effect placed on enemies by when hit by , , or that causes the skill's effects (domination, detonation, and gain power charge respectively) to activate if the enemy dies within a short time after the hit
- The effects granted by some items, like Onslaught and Unholy Might.
- The bleed effect of  .
- The poison effect of .
- The damage reduction and mana cost of .
- Map effects like Creeping Darkness
Incomplete list of things that are not buffs or debuffs
- The Ignited, Chilled, Frozen, and Shocked elemental status effects
- The life & mana recovery from flasks
- Any effects that result from modifiers on life & mana flasks, such as the movement speed from the "of Adrenaline" suffix
- Endurance, Frenzy, and Power Charges
- Viper Strike and Adder's Touch DoT Effects