Effect updates and description changes can be seen here.
Undertale OST - NGAHHH! Extended

Undertale OST - NGAHHH! Extended

0:00 - 0:05

Undyne is a great monster that can quickly change the tide of war. She has fairly hefty pricetag, however with her ability to deal 8 damage split randomly upon the enemy monsters on the field, she can quickly kill off or weaken most of the enemy simply by entering play.


Best played when the enemy has a total of 8 HP among their monsters, so she can clear out the entire board. She can also be used in combination with Asgore, although that comes at an enourmous price of 28G. Undyne works very well against monsters with Dodge (this being Sans and Sad Dragon only), as because of the 8 × 1 damage ability, they will most likely die because of it. This card is useful in most decks, however particularly so with Determination and Justice.

Creatues like Mad Dummy cannot be killed by Undyne's ability as it distributes the attack 1 damage at a time upon the monsters.

Card Skins

Card Skin (Undyne)

Sexy Fish

  • Sexy Fish (by Moonlightring)
    • Only available during April Fools.
      Card Skin (Undyne) 2


  • Justice (by Moonlightring)
    Card Skin (Undyne) 3

    Spear of Justice

  • Spear of Justice (by Darky)
    Card Skin (Undyne) 4

    Summer Undyne

  • Summer Undyne (by Moonlightring)
    Card Skin (Undyne) 5

    Pirate Undyne

  • Pirate Undyne (by Moonlightring)
    • Only available during Halloween.
      Card Skin (Undyne) 6

      The Sheriff

  • The Sheriff (by Jake Horror)


  • Beta 31.0 made her count as a Royal Guard.
  • Undyne is one of three cards with a Skin limited to April Fools Day. The others are Lancer and Ralsei.
    • Undyne is also the only card with 2 Skins restricted to a holiday, the other being Halloween.