As the only female pirate in John Silver's crew, her physical alien appearance resembles that of a gray brain and its stem, only added with a pair of arms, which serve as her only means of walking mobility (however, this does not seem to affect her services to Silver, which involve handling guns or knives). During the voyage, the ship encounters a supernova. Jim (while securing lifelines of all pirates) saves Silver from falling just in time. The supernova then devolves into a black hole, where Arrow falls. The burst of shock waves and maximum engine power enable Amelia to pilot the ship to safety. Amelia mourns the loss of Arrow, and suspects Jim of failing to secure the lifelines, while Arrow's line was actually cut by Scroop. Meanwhile, Krailoni and the pirates corner the group here; using a back door, Jim, B.E.N., and Morph return to the ship in an attempt to recover the map. She is also one of the only few pirates to survive during their mutiny, as she is arrested by Captain Amelia and Dr. Delbert Doppler for her crimes alongside the remaining crew. Despite her arrest, Krailoni is last seen cheering along with the remaining crew for Jim for saving them from the exploding planet.
Krailoni and Longbourne climbing
Krailoni, Fayvoon, Turnbuckle, and Blinko listening to John Silver's interesting stories
Scroop, Krailoni, Hedley and Torrance angry
Krailoni restraining B.E.N.
Silver, Jim, Ben, Morph, Turnbuckle, Onus, Krailoni, Blinko, Hedley, and Torrance finding the treasure
Krailoni's defeat along with the other surviving pirates