Undertale is an RPG created by solo developer Toby Fox and released in 2015. It follows the story of a nameless human child as they fall into a world of monsters and attempt to make their escape.
Fox's game combines top-down Earthbound-style exploration and character interaction with turn-based combat that also incorporates bullet hell-style dodging mechanics.
Its key selling point is the ability to progress through the game without killing enemies; players usually have the option of subduing enemies by talking to them or through other methods instead.