Ferocious Pirarucu is a species of Fish native to Termina that appears in The Legend of Zelda: Majora's Mask 3D. Spoiler warning: Plot or ending details follow. It is one of two Boss Fish that be caught in the Swamp Fishing Hole (the other being Lord Chapu-Chapu). Its appearance is random and can be found on all days. If it appears, it can be hooked by hooking smaller fish (either Groovy Carp or Termina Bass) near it (without actually landing the smaller fish). Since it is a Boss Fish, Boss music will play when it is hooked and is one of the hardest fish to land in the Swamp Fishing Hole. Spoiler warning: Spoilers end here.