Aura

The Aura is a passive modifier to units that are near the aura source. Some auras buff allies, increasing their effectiveness in battle, while others debuff enemies, hindering their efforts on the battlefield. In almost all cases aura effects are unique, and cannot be stacked.

An exception to this rule is in the event that multiple champions are carrying an item with the same beneficial aura effect, each of those two champions will receive two instances of the aura buff: one from the item they are carrying, and a second from the aura of their ally. If a champions is near both of the champions with the same aura item, it will only receive one instance of the aura. No champion can ever receive more than two instances of a unique benevolent aura, regardless of how many nearby allies are providing the buff. Aura effects that are not provided by items, such as the damage provided by the summoner spell Rally, can never stack.

As of patch 1.0.0.107, 's effect is considered an aura, and no longer stacks.

Global Auras

 * Increases the Movement Speed of all allied champions by 3%.
 * Increases experience gain of all allied champions by 8%.
 * Increases gold per minion kill on all allied champions by 2.
 * Increases experience gain of all allied champions by 8%.
 * Increases gold per minion kill on all allied champions by 2.
 * Increases gold per minion kill on all allied champions by 2.

Area of Effect Auras

 * increases surrounding allies' magic resistance by 16
 * provides bonus armor to himself and nearby allies
 * give nearby allied Turrets and Champions 6 / 12 / 16 / 22 health regeneration per 5 seconds
 * grants nearby allied champions bonus attack damage and ability power
 * grants nearby allied champions bonus armor and magic resistance
 * grants nearby allied champions bonus movement speed
 * grants magic resistance reduction to nearby enemy champions
 * grants nearby allied champions bonus attack damage and ability power
 * grants nearby allied champions bonus armor and magic resistance
 * grants nearby allied champions bonus movement speed
 * grants magic resistance reduction to nearby enemy champions
 * grants magic resistance reduction to nearby enemy champions

Beneficial auras

 * Unique Aura: +12 Armor, +15 Magic Resistance and +8 Attack Damage to nearby allied champions. +270 HP, +18 Armor, +24 Magic Resistance. 1925 Gold.
 * Unique Aura: +10 HP regen to nearby allied Champions . +17% LS. 800 Gold.
 * Unique Aura: +20 HP regen, +9 MP regen to nearby allies. +430 HP, +450 MP. Unique Passive: When you cast a spell, you regenerate 50 health and 20 mana over 2 seconds. This effect has a 3 second cooldown. 2250 Gold. (This item was removed in V1.0.0.107)
 * Unique Aura: +7.2 MP regen to nearby allied Champions. 475 Gold.
 * Unique Aura: +12 MP regen, +15% CDR to nearby allied Champions. +520 HP. 2285 Gold.
 * Unique Aura: +30 Ability Power and 15% Spell Vamp to nearby allied Champions. +40 Ability Power. 2400 Gold.

Offensive auras

 * Unique Aura: -20 Magic Resistance to nearby enemies. +70 Ability Power, +60 Magic Resistance. 2650 Gold.
 * Unique Aura: -20% Attack Speed to nearby enemies. Unique: 25% CDR. +99 Armor, +500 MP. 2775 Gold.
 * Unique Aura: +40 Magic Damage per second to nearby enemy units. +45 Armor, +450 HP.

Both offensive and beneficial auras

 * Unique Aura: +20% Lifesteal, +20% Attack Speed, and +30 HP regen to nearby allied champions. Unique Aura: -20 Armor to enemies. +20% IAS. 2550 Gold.