Gensou Goroshi is the Japanese name for Imagine Breaker, the signature ability of Kamijo Touma, protagonist of Kazuma Kamachi's light novel series A Certain Magical Index, first published in 2004 and adapted into anime by J.C.Staff in 2008. The phrase is shouted when his right hand negates magic and esper abilities. Clips of the line spread through anime versus debates, AMVs and short-form edits, where it became shorthand for nullification. It endures because it condenses the series' underdog theme into two seconds of defiance.