Tiny and Big: Grandpa's Leftovers is a puzzle platform video game, which originally was released as a tech demo titled Tiny & Big: Up That Mountain in 2010. In the game players have to manipulate levels with a handful of tools to solve puzzles which are three dimensional. The main protagonist of the game is an inventor named Tiny, who has to get back his possession, which is a magical pair of briefs. These briefs were left to him by his disappeared grandfather from his rival Big who intends to rule the world.
In the game, the player has the ability to use an invention of Tiny called The Tool which has three functions: a strong laser, a grappling rope for pulling objects and a rocket for pushing objects forward. This Tool is the main item in the game as it helps not only to solve various puzzles but also defends Tiny from attacks of Big. There is also an artificial intelligence named Radio who acts as a mentor, providing prompts and hints for the player in order to progress.