Co-op vs. AI

Co-op vs. AI is a game mode in League of Legends where a team of five human players are matched against a team of five computer-controlled players, commonly known as bots.
 * Co-op vs. Ai.png on the Co-op vs. AI banner.]]

Description
Co-op is available on The Crystal Scar (Dominion mode), Twisted Treeline, or Summoner's Rift (classic mode). There are two difficulties to pick from, Beginner and Intermediate. A player can either play alone or invite their friends to join them. If the composed team has less than 5 players, the matchmaker searches for other players wanting to play at the selected difficulty. The co-op matchmaker works similar to normal games, but considers the players level instead of their Elo Rating. First Win of the Day IP bonus is available and Elo Ratings are not affected.

Co-op vs. AI rewards are slightly higher than custom games but lower than normal games or ranked games. Here are the current rules for Co-op vs AI rewards:
 * All summoners can earn unlimited rewards per day in Co-op vs. AI. However, level 15+ summoners can only earn 75% of the normal Co-op vs AI rewards after 180 minutes.
 * The following modifiers are applied based on summoner level and bot difficulty setting. These percentages represent how much of the standard reward is received:

There is pool of 50 champions that the bots can be picked from. They are as follows, listed within categories according to five major roles (refer to AI roles' classification):

History
Co-op vs. AI was first announced on LeagueofLegends.com on January 20th, 2011, as a new game mode intended to prove a harder challenge and training method for players rather than just the bots available through the custom game option.

A match showing a fight between some of the new bots versus mid-level Riot Employees was announced on February 4th to take place on February 9th. This battle was streamed through Own3d, and resulted on a close (and sketchy) victory for the Bots.

It was intended to be released on the week following the V1.0.0.111 Patch, but it was delayed because the European servers were not ready to take on the increased stress that would be caused by the game mode.

It was finally released on a Thursday, on March 10. It supported two difficulty settings, Beginner and Intermediate, and a pool of 12 bots available only on Summoner's Rift.

Rise of the Bots Update
On January 24, 2012, Riot released a news post announcing an update to the Co-op vs. AI game mode. This update was put in place on February 1, 2012, with the V1.0.0.133 patch. The new features and upgrades included the following:
 * Bots made available in the Dominion game mode, which its co-op option was unavailable at the initial launch until this patch.
 * More intelligent bots with increased map awareness, capability to use skillshots as well as more summoner spells and active items.
 * The flat IP penalty for Co-op versus AI games was removed. The rewards were also changed to make the mode more attractive.
 * Increased the roster of bots from 12 to 40. Also, more champions are being added in the subsequent patches regularly.