Were you looking for its stronger counterpart, Supergoon?
Seagoon is one of several bosses encountered in FNaF World.
Seagoon, oddly enough, has an appearance similar to that of a cephalopod, with a large head and purple tentacles. It has an upper set of teeth, bumps on the top of its head and nostrils, and blackish eyes with white pupils along with sinister big eyebrows. Since Seagoon's boss fight takes place in the water, there are waves under it.
Basic blue bash attack
Deals medium damage to a single party member.
Kills all party members under 30% health.
Seagoon has a stronger counterpart named Supergoon.
Contrary to what Fredbear said, Seagoon isn't found randomly, he instead moves in a path, then reverses to the starting spot. If the player stumbles upon Seagoon's path, the battle with begin.
Due to the fact Seagoon can start a battle if the player is in his path, he has a chance to start a battle when the player receives notice that a challenger is approaching. This will prevent the player from being able to fight the challenger if Seagoon initiates battle before the challenger does.
Seagoon is one of the five bosses that are considered optional bosses, since the player doesn't need to defeat it to complete the story. The other four being Auto Chipper, Eyesore, Mad Endo and Gold Endo.
However, due to the fact that Seagoon appears only occasionally, if it appears, the player will have no other option than defeat it to proceed in the game. The same happens with Gold Endo.