Finn Mertens was born on Hub Island to Martin Mertens and Minerva Campbell. After Martin fled with Finn from the island, he abandoned him, and Finn was raised by Joshua and Margret the dog, alongside his newfound adopted brother, Jake the Dog. As they matured they become the loyal guards of the candy kingdom under princess Bubblegum. Many adventures ensued until Finn tried to see his father again, Finn lost his arm, which would be replace by the grass sword, until that fuse with another sword (blah, blah, BLAH!!!!). Now he has a robotic arm.
Swordsman: highly trained with a sword, a rapier, he can also do many well trained slashes to sever stone and metal with one strike, taut by his mentor, rattelballs
Highly athletic and highly acrobatic
Cybornetic Arm: he has a cybernetic arm that has: ear piercer, toaster, spin down dice, pasta maker, fan, cursed scroll, hard drive, small guitar, sad marionette, rock drill, weed wacker, dehumidifier, deep tissue massage, torque wrench, crab claw settings, and many more