Fern (full title: Fern the Human, formerly known as Grass Finn) was the result of Finn's Grass Sword and Finn's normal Sword merging into one being. He makes his first appearance at the end of "Reboot."
Return of the Weirdmageon Cult[]
Chapter 2[]
Fern was active in Toffee's plan as he thought Shark Boy and Lava Girl once and Craft the 2nd time.
Chapter 3[]
Sprig and Anne lead the group by using the toad foot prints and running up ahead while Marcy, Ibuki and Luz arming themselves to dealing with the toads as they enter the Whole foods to see everyone imprisoned and inchained in the stores. I-Rok and Fern are also there observing with the toads to make sure the people of Big City Greens do the work for Whistler to keep making money. Sasha shows up with Grime which Anne and Sprig decide to take on for Marcy, Luz and Ibuki to find Cricket. Fern does hold down Ibuki and Marcy leaving Luz to go find Cricket. I-ROK does catch Luz, but Luz doesn't let her self be pushed and makes for her cowardice regarding Cricket and uses her glyphs to take out I-ROK before running to find Cricket
Chapter 4[]
Marcy who managed to avoid the obvious traps sent by the Cult and is deeper in the factory finds out that The Boiling Isles is subject to Industrailism at the hands of Chip Whistler hence why He evicted the Owl House and left it there after he was done. Relaizing she could be watched, moves with her unknownigly being right. As Immortus had located her with Fern, Pinstripe and the Gang Green Gang and sents them to capture Marcy Wu.
Lalo springs the real real trap and has Grodd and Fern restrain them again. Lalo calls Luv and Promethus who have been the ones controlling the situation.Eda shows up and saves Luz and holds Luv down. Fern tries to impale Eda, but Eda just sets him on fire with a mere yawn unimpressed with a grass knight