Adventure Time Wiki
Adventure Time Wiki

This article is about the Finn Sword. You may be looking for Finn's swords.

The Finn Sword is a sentient sword created by a paradox in "Is That You?", after Finn sacrifices an alternate-reality version of himself to bring Prismo back to life.


The Finn Sword first appears in "Breezy" during Finn's vision, when Finn awakens to Breezy's final song. However, instead of seeing Breezy in her Queen form, he has a vision of Princess Bubblegum holding the Finn Sword.

In "Is That You?", visiting a much more elaborate version of Prismo's Time Room, created as a "Plan B," Finn makes a choice to save Prismo by creating a paradox that vaporizes his dream world duplicate. Instead of turning to dust, Finn's body turns into a sword, dubbed the Finn Sword by Prismo.

In "I Am a Sword", it was lost until being found by Bandit Princess, who used it to steal gold and kill people. Finn accidentally stabs the Finn Sword with the Grass Sword, rendering it inactive. The Finn in the sword is seen at the end of The Music Hole, suggesting that the sword's inactivity is the alternate Finn's choice rather than actual destruction.

In "Reboot" and "Two Swords", it is revealed that there is a little Finn living within the space of the sword, and the grass sword once again touches the Finn Sword. This results in the creation of a strange grass humanoid. Due to having Finn's memories he later takes on the name and personality of Finn but starts to become a different person known as Fern. Fern was killed (shattered into grass pieces) in "Three Buckets," but was resurrected by Gumbald as seen in the episode "Seventeen."

After Fern's destruction in "Come Along With Me," his remains take the form of a seed shaped like the Finn Sword. That night, Finn and Jake plant the seedling together, which causes a massive new tree to sprout, with a remade Finn Sword embedded in its branches. Many years later into the distant future, Shermy and Beth find the sword on the top of the tree.


The sword is first used in "Dentist", and it is shown to have Finn's dream world duplicate trapped inside of it, able to speak directly to Finn from the blue sphere between the hilt and blade it is encased in. In "Crossover," it is shown that other characters besides Finn are able to hear the Finn Sword's voice. Also, while Finn is using this sword in battle, his physical attributes are double what they are without it. This is more than likely linked to the dream world duplicate inside it.

It is still unknown which mystical attributes if it does have them, the restored Finn Sword born by Fern's seed after a millennium has, and if they will work with Shermy, its current owner and possible reincarnation of Finn himself.

Episode appearances


  • The Finn Sword and Grass Sword merged together, creating Fern. Technically, the Grass Sword was used to make the Finn Sword, as the alternate Finn had the grass sword in his right arm when he became the sword.
  • Also, the Finn sword resembles the Blue Catalyst Comet reincarnation of Finn's form where the sword's handle is like the asteroid and the blade is like the flame body. This makes sense since even there is a small Finn inside the sword's handle.