How to Dress Like Undyne

Female Video Games

Best Undyne Costume Guide

Undyne is a humanoid monster that resembles a fish in the 2015 role-playing indie game, Undertale. She is the leader of the Royal Guard of the Underground, a realm where monsters reside. Her powers include spear telekinesis, enhanced strength, and soul manipulation. Her goal in the game is to kill Frisk and other humans to take the last soul. Possession of the last soul is needed to break the barrier between the Underground and the human world. Her other actions in the game depend on the choices made by the player. She can be controlled to support Frisk in defeating Asriel Dreemuur, son of Asgore, who is the king of the Underworld.

Get the look of the fish-like monster with this Undyne costume guide. Even if you are having second thoughts about wearing armor, the Undyne cosplay guide represents her more laidback outfit. This outfit includes Gray Jeans, Black Tank Top, and our red Cosplay Boots.

Undyne Cosplay Costumes

Undyne has royal blue scales covering her entire body with bright red hair styled in a long ponytail. She has a pair of protruding teeth and fins on the side of her head. Covering Undyne’s left eye is a patch that she uses to mask a lost eye perhaps or that maybe just for her style. The outer layer of her eye is yellow. These turn black when she is severely wounded. In her first appearance in the game, Undyne wears armor with a helmet, gloves, and boots.

In her casual mode, she wears a black tank top, blue pants, and a pair of red boots with yellow stripes. But, Undyne also has another form in which her sclera becomes black, and her pupils turn white. Her eye patch is taken off, revealing an empty eye socket where flashing lights are visible. Undyne’s casual outfit is easy to follow! Find an Eye Patch, Dragon Ears, and Body Paint at a costume shop. Her clothes are basic enough to find just about anywhere. Complement the look with a red wig and spear that can most likely be found online.

Undyne Costume Tips & FAQs

Plunge into the adventurous world of Undyne from “Undertale” with our specially crafted costume guide FAQ. This guide is here to assist you in embodying the valiant and passionate fish-like warrior. Whether you’re a seasoned cosplayer or a newcomer, these tips will help you capture Undyne’s unique style and spirit, perfect for conventions, parties, or just for fun.

Undyne's costume consists of a black tank top, blue shorts, and a red heart locket. She is also known for her distinctive fish-like features, including blue scales, sharp teeth, and a red eye. Her look is completed with a pair of red arm guards and black boots. Don't forget her most iconic feature: a bright, cyan-colored spear.

To mimic Undyne's fish-like features, use blue face paint or makeup for the scales, which can be applied in a pattern along the arms and face. For her sharp teeth, you could use dental-safe putty to create pointed teeth effects. Colored contact lenses can be used to replicate her red eye.

Undyne's spear can be crafted from materials like foam, PVC pipe, or lightweight wood, painted cyan. For the arm guards, use foam sheets or lightweight plastic, which can be cut and shaped accordingly, then painted red. These materials are ideal for a balance of durability and comfort.

Undyne has a short, spiky, and bright blue hairstyle. A short blue wig can be styled with hair gel or spray to achieve her spiky look. If you prefer to use your own hair, consider temporary blue hair dye and styling products to get the desired effect.

To truly capture Undyne's character, consider using some of her memorable quotes like, "I'll let you grab some dinner with me first!" or "NGAHHH!!" Her gestures are often bold and dramatic, reflecting her warrior spirit and determination. Striking heroic poses and mimicking her combat-ready demeanor can add authenticity to your portrayal.

About Undyne

As the leader of the Royal Guard, Undyne is serious when it comes to her duty—to kill the protagonist and take the last soul needed for Asgore to break the barrier. But she is also an honorable and friendly being, especially to Alphys, Papyrus, and the Royal Guard. Undyne is fiercely competitive but remains kind and caring to those whom she considers her friends. She harbors a secret love for Alphys, the royal scientist of the underground. Undyne has other interests outside of her job in the Royal Guard. She likes to train and cook with Papyrus, hang out with her friends, and stand on a crag talking to herself.

With her spear telekinesis, Undyne can summon spears of blue light energy in unlimited amounts. She also has enhanced strength that has enabled her soul manipulation abilities to allow her to control the soul of another being.


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