Undertale is an indie role-playing game released in 2015 by Toby Fox, and the Gaster Blaster became one of its most memorable battle effects. In the game, Sans summons floating skull devices during his boss fight, and each one fires the beam heard in this clip. The weapons are named for W. D. Gaster, a mysterious hidden character surrounded by fan theories. Clips of the blast later spread through fan animations, edits, and soundboards, where the short charge and explosive payoff made it ideal for pranks and dramatic meme moments.