Buff

A buff is any status effect given to a champion or a minion that gives them a beneficial boost in their performance. A buff that gives negative effects is called a debuff. Buffs can boost almost any attribute of a character, such as health, mana, damage, and ability power. Positive changes to champions or items in the Patch Notes can also be called buffs, while negative changes can be called nerfs.

Some buffs can stack a predetermined number of times while other buffs may not be stacked. This means that repeated applications of the buff to the same target will not grant him any increased effect but will only cause the buff duration to reset. Most buffs are temporary but some buffs may last indefinitely (such as boosting her attack range). Other buffs are lost upon champion death.

There are several sources for buffs and debuffs in League of Legends, specifically items, abilities, spells and epic monsters.

Item buffs
These are buffs that come from the items you can buy from the shop in exchange for gold. Every item will boost one or several statistics by default however there are additional effects on some. These come in the form of passive effects that are persistent as long as the item is not sold. Auras boost not only yourself, but your allies as well. And active effects that boost you and sometimes your team mates significantly for a short period of time. These active effects usually have a cooldown attached to them.

Ability buffs
These are champion abilities which increase stats when acquired with levels. These come in the same category as item buffs; Passive, Aura and Active. These abilities usually grow stronger with more ability power, attack damage, and/or levels.

Summoner spell buffs
These are summoner spells which increase stats when used or coupled with the right masteries. For example, increases your movement speed. is the inverse case, as the ability power bonus is only in effect when is on cooldown.

Monster buffs
These are temporary buffs acquired by slaying jungle monsters. For example, the grants the  buff. In this case, the monster usually has swirling colored runes around it. Other monsters, specifically and Vilemaw, grant a powerful buff to the entire killing team.

Dominion
With the development and ultimately, release, of the Dominion gametype, new kinds of game elements will be brought to the table. This also includes the new buffs.

Shrines
Shrines are areas on the Crystal Scar that grant a short duration movement speed bonus to champions that pass through them. These shrines are neutral and can be used repeatedly throughout the game.

Relics
Relics come in two forms: lesser and greater. Lesser relics provide a small replenishment in health and mana for the champion that picked up the relic. Whereas greater relics provide a personal shield and damage amplification.


 * Lesser Relics spawn on specific locations at short, regular intervals, and can be picked up to restore health and mana. Champions from either team can acquire a health relic simply by moving over it. They are available 2 minutes into the game, and after consumption respawn every 30 seconds.
 * Greater Relics are a pair of powerful team specific objects that spawn at the center of the map. While the Greater Relics spawn less frequently than Health Relics, they provide powerful offensive bonuses that help assault particularly well-fortified capture points. Acquiring these Greater Relics requires a brief channel time. They are available 3 minutes into the game, and after consumption take 3 minutes to respawn. Capturing a Greater Relic takes 10 seconds.