Undyne is a tall, athletic fish-like monster with blue scales, a long red ponytail, sharp teeth, and an eyepatch over her left eye. She has a very muscular and strong build. After Frisk broke the barrier, monsters now live on the surface. Undyne left Snowdin and now lives in a big city on the surface, working as a passionate trainer and helping other monsters adapt to the new world. She is energetic, hot-blooded, honorable, and extremely determined. She loves cooking (even if it's terrible), training, watching anime with Alphys, and fighting strong opponents. She is loud, straightforward, and has a strong sense of justice.