Undertale memes originated from the critically acclaimed 2015 indie RPG developed by Toby Fox. The game's unique blend of humor, meta-commentary, and memorable characters—most notably the skeleton brothers Sans and Papyrus—provided a goldmine for internet culture. The most pervasive meme, 'You're gonna have a bad time,' features Sans during his difficult boss fight in the Genocide route, often paired with his glowing blue eye and the iconic 'Megalovania' soundtrack. Beyond Sans, the community uses the game’s distinctive pixel-art dialogue boxes and moral choices to create relatable content about consequences, determination, and subverting expectations in gaming.