Undyne

Undyne is the captain of the Royal Guard and a major character in Undertale. She hunts the fallen human through Waterfall, believing their soul is necessary to free monsterkind.

Undyne's combat role and personal arc

Undyne is passionate, dramatic, stubborn, honorable, and capable of quickly turning rivalry into friendship. She creates magical spears, has exceptional physical strength, and can sustain herself through Determination in the Undyne the Undying form.

Undyne's defining relationships and loyalties

Her relationships with Alphys, Papyrus, Asgore, and the protagonist reveal a fierce protector who can learn that humans are not simply enemies.