Finn is the second boss in the Donkey Kong Adventure mode of Mario + Rabbids Kingdom Battle. He is a shark-like Rabbid with a broken hook in his "shark mouth", a missing right eye, and a fishing line around him. He is first seen gorging on a large pile of Bad Bananas; when spotted by Donkey Kong and co., he immediately attacks them.
Finn acts somewhat like a Smasher, as he moves towards any character that attacks him, damaging them if he reaches them. His main attack involves him swinging his hammer in circles when near characters, and then moving close enough to another character to attack them on the next turn.
When defeated, Finn will defuse from the item he was merged with: a rubber shark.