Rory Alderton is a senior animator at League of Legends developers Riot, where he's one of the people responsible for putting the moves in the game's Champions.
In a post over on Riot's site, he goes into great detail on the process behind animating the game's characters, including the revelation that the Champions are animated by hand-keyed animation, "because it's integral to maintaining our in-house style and helps us deliver smooth and instant animations that don't affect League's gameplay".
Fans of animation, or just League in general, can check out more on Rory's work at his post.