Leeroy Jenkins is an Internet meme named for a player character created by Ben Schulz in Blizzard Entertainment's MMORPG World of Warcraft. The character became popular due to a video of the game that circulated on the Internet. The phenomenon has since spread beyond the boundaries of the gaming community into other online and mainstream media.
The video was released by a World of Warcraft player guild, featuring a group of players discussing a detailed battle strategy for their next encounter while Leeroy is away from his computer. This risky plan is needed specifically to help Leeroy, yet it is ruined when Leeroy returns and, ignorant of the strategy, immediately charges headlong into battle shouting his own name in a stylized battle cry. His companions rush to help, but Leeroy's actions ruin the meticulous plan, and all of the group members are massacred.
The Internet phenomenon started with the release of the video clip called A Rough Go to the World of Warcraft game forum in a thread titled "UBRS (vid) ROOKERY OVERPOWERED! blue please.", which jokingly presented the video in a serious context. The thread requested that other players provide help with strategy and that Blizzard reduce the difficulty of the encounter. The video spread as an Internet meme, and Leeroy's response to the other players' chastisements, "at least I have chicken", was also much parodied.
When asked about his actions in the video by National Public Radio, Ben Schulz said the players "were drinking 40s and just yelling at each other." As time went on some began suggesting that the video may have been staged. Schulz has neither confirmed nor denied this.
The character's popularity resulted in his inclusion in the World of Warcraft Trading Card Game released on October 25, 2006 with art by Mike Krahulik. Reflecting the video in which he appears, Leeroy is a detriment to the rest of the player's team, exhausting them for the current and following turns. For gameplay reasons, his effects are not entirely negative: although no one else can attack, Leeroy can attack instantly should the player repeat Leeroy's famous shout, and his attack is unusually high compared to the cost of playing him. However, his health is such that opponents should deal with him easily on subsequent turns. Upper Deck Entertainment released a World of Warcraft Miniatures game in late 2008, which included a Leeroy Jenkins figurine. As a reference to Leeroy's famous claim, the figure is seen holding a chicken leg in his left hand.
Blizzard named a card after Leeroy Jenkins in their popular online card game Hearthstone: Heroes of Warcraft. When entering the battlefield, Leeroy gives his famous battlecry. While attacking, he says "Time's up, let's do this!" And when he dies, he says, "At least I have chicken." In addition, the adventure mode "Blackrock Mountain" added a new game board themed on the mountain. In the bottom right section there is a pink tabard with a white heart lying on the ground, a reference to the guild Leeroy was in, <PALS FOR LIFE>.
The August 2005 issue of PC Gamer UK featured an article on the video, titled "The Ballad of Leeroy Jenkins". The article took the position that the video was designed as a negative commentary on the kind of "nerd-guilds" that meticulously and statistically plan out raids with all the seriousness of actual military tactics. They added that they felt Leeroy is in fact the hero of the piece, acting against the geekiness of his guild.
Blizzard eventually paid tribute to Leeroy within World of Warcraft itself, creating the achievement "Leeeeeeeeeeeeeroy!", which awards the title of "Jenkins" to players who kill 50 of the rookery whelps from the video within 15 seconds. Also, in the new expansion "Warlords of Draenor", Leeroy returns as a non-player character and will join the player's garrison if they help him find the Devout Shoulders he was seeking in the video.
Leeroy Jenkins went mainstream when he was mentioned as part of a clue on the November 17, 2005 episode of the game show Jeopardy! as part of their college week tournament, though no contestant rang in. The meme spread further in 2009, when the Armed Forces Journal published an article titled "Let's Do This!: Leeroy Jenkins and the American Way of Advising". The article, by Capt. Robert M Chamberlain, links Jenkins to the American approach to advising Iraq.
Tanner Higgin, doctoral candidate at the University of California, Riverside uses the Leeroy Jenkins video and subsequent discourse to "teach game analysis, more specifically the analysis of gamic race".
The National Geographic Channel series Inside Combat Rescue, which aired in 2013, embedded with an Afghanistan deployment of USAF Pararescue, outfitting them with micro-cameras that recorded them on their missions. Their radio call sign is always "Pedro" and their radio alert warning of a rescue mission started with the audible, "Leeroy Jenkins". It is used as a battle cry equal to "Let's do this!"
Sportscaster Michelle Beadle has a Pug named Leeroy Jenkins. 
In the Phineas & Ferb episode "The Klimpaloon Ultimatum", a homage to Leeroy Jenkins takes place in which the characters devise a plan to attack an evil facility, only for their teammate Buford Van Stomm to go charging in with no strategy whatsoever while yelling his name. After they are captured, Buford responds that he "was using gamer strategy"; he does the same thing later in the episode.
In Murtaugh, episode 19 of How I Met Your Mother's fourth season, main character Barney Stinson yells his own name in the same war cry-like fashion as Leeroy Jenkins, upon making a "gentleman's agreement" with Ted Mosby.
In the 20th episode of the 4th season of The Cleveland Show, Rallo exclaims Leeroy Jenkins while playing an imaginary game attacking a battleship.
In the 2nd episode of the 6th season of Psych, it is discovered that the suspect they are looking for is named Leroy Jenkins. When Shawn discovers this, he yells Jenkins' name in the style of the video.
In the opening mission of the game Mass Effect, the non-playable character Private Jenkins is the first casualty after he walks directly into an ambush, having ignored any previous advice the player can choose to give him about being cautious.
In Ernest Cline's novel 'Armada', the main character Zack Lightman screams "Leeroy Jenkins" as he charges in during a video game session of Armada.
In Season 5, Episode 6 of 'Duck Dynasty,' John Luke yells "Leeroy Jenkins!" as he ignores Jase's paintball battle plan and charges off on his own.
- Joel Warner. "The Legend of Leeroy Jenkins".
- Abduhl (May 10, 2005). "WoW BlueTracker: UBRS (vid) ROOKERY OVERPOWERED! blue please.". Retrieved September 18, 2009.
- "My ROFLCon Weekend: Breakfast with Tron Guy". The Bryant Park Project (National Public Radio).
- "Leeroy Jenkins". p. WoW TCG Browser. Retrieved 18 October 2013.
- "World of Warcraft Minis Checklist (Alliance specs & attributes)". 27 January 2009. Retrieved 8 March 2010.
- "Leeroy Jenkins". p. World of Warcraft Miniatures Game Checklist. Retrieved 8 March 2012.
- Pearson, Craig (August 2005). "The Ballad of Leeroy Jenkins". PC Gamer UK.
- Amanda Miller (2008-10-14). "Five easy achievements you can snag right now". WoWInsider. Retrieved 2008-10-16.
- "Leeeeeeeeeeeeeroy...?". Wowhead.
- (2006-11-18.) "Guerilla gaming." Guardian Unlimited (news website). Mentions the Jeopardy question without specific details. Retrieved on 2007-10-07.
- Chamberlain, Robert (June 19, 2009). "Let's Do This! Leeroy Jenkins and the American way of advising". Retrieved 2009-06-19. (registration required)
- Higgin, Tanner (September 17, 2009). "How I Use Leeroy Jenkins to Teach Race in Videogames". p. MediaCommons.
- "Michelle Beadle on Twitter". Twitter.
- Leeroy Jenkins on YouTube (broken sound as of May 2015; higher-quality copy here: Leeroy Jenkins (High Quality) on YouTube
- The Legend of Leeroy Jenkins, article at Denver Westword News