Undyne (/ˈʌnˌdaɪn/ UN-dyne), known as StrongFish91 on the UnderNet, is a fish-like monster that leads the Royal Guard. Clad in her full suit of armor, she pursues the protagonistthrough the entirety of Waterfall and is frequently evaded or inadvertently thwarted by the Monster Kid.
Role in Series Edit
Undyne makes her first appearance in Sonja in the Underground when she found Sonja and told her about Vixion and her Shadowlings attacking the Underground. So she gathers her friends, Sans, Papyrus, Asgore, Alphys and Toriel to help stop Vixion and her Shadowlings attacking. She joins with Sonja and the others after the events.
Undyne is passionate about everything that she does. She acts quickly on her ideas and is steadfast in her beliefs. Though she wants to defeat the protagonist, she also tries to be fair and offers an explanation of how Green Mode works. Asgore taught her the value of pacifism, which is why Undyne sees the protagonist as "a wimpy loser with a big heart." When the protagonist first encounters her, she fights to further Asgore's plan of collecting seven human SOULs but, if the protagonist shows mercy, Undyne just as quickly defends them from Asgore.
She loves to help others and mentors Shyren and Papyrus in various skills. Undyne dislikes puzzles, loves japes, and enjoys anime, an affinity she shares with her romantic interest, Alphys. Since Alphys told Undyne that anime is actually human history, Undyne regards human history as exciting and cool.
Out of all encountered monsters, Undyne possesses the most Determination. She melts before her death, implying that her body cannot handle the amount of Determination she has.
Sonja Farrington Edit
She and Undyne are great friends with each other. Undyne is like a older-sister figure of Sonja, even though Sonja has Cleo. She has really good terms with her too.
Alphys and Undyne have crushes on one another. Undyne first met Alphys in the Garbage Dump, listening for hours about where she thought the abyss there led. The two became close friends soon after, with Alphys introducing her to anime at some point. They hang out often, and Alphys uses the seagrass throughout Waterfall to make a special frosty treat for Undyne. Alphys and Undyne also worked together to create some of the puzzles in Waterfall.
They nearly kiss in the True Pacifist Route, but Toriel interrupts them and tells them not to kiss in front of the protagonist.
Undyne thinks of Papyrus as a close friend. She is impressed by his persistence and trains him in cooking, but is concerned about his well-being and secretly does not want him to join the Royal Guard because she believes that he is too nice to fight. She teaches him how to cook in hopes that he changes his mind about joining the Royal Guard. Undyne sometimes enjoys messing with Papyrus, but she often forgets that he usually takes things literally. She is heartbroken and infuriated if the protagonist kills Papyrus during a Neutral/Genocide Route.
Even though Asgore is her boss, Undyne sees him as a friend and knows his favorite type of tea. When she was younger, Undyne challenged Asgore to a fight but could not land a single blow on him. She was humiliated because he did not fight back and only dodged her attacks. Asgore then offered to train Undyne and eventually promoted her to head of the Royal Guard.
After Toriel fireballs Asgore in the True Pacifist Route, Undyne consoles him because he is crying.
Queen Vixion Edit
Undyne is enemies with the Vixion like Sonja and the others. She wants to get her revenge for defeating her and she finally got her revenge when she defeated Vixion.
Shadowling Trio Edit
Undyne is also enemies with them since the Shadowling Trio are Vixion's henchmen. She gets satisfied and is very pleased of Pixie Dark and Moona fighting or bickering with each other.