The Yaarctopus can be found in one of the Coral Reefs that generally spawn in an Ocean (Shallow) biome. He is found lying on a Coral Rock wearing an eyepatch, a small pirate hat, an earring on the side of his head, and a wooden pegleg on one of his tentacles. He is immune to any damage and cannot be attacked. He is the Shipwrecked equivalent to the Pig King.
During the day, the player may trade any Fishes, Trinkets, and certain Fish Crock Pot recipes with the Yaarctopus in exchange for an Octopus Chest. After handing in one Item, the Yaarctopus will fall asleep for the rest of the remaining day and cannot again be traded with until he wakes up. The Yaarctopus will shake its head when the player attempts to trade items other than fish or trinkets.
For each Fish given the chest will always contain one Dubloon in addition to one of Seaweed (38.46%), Seashell (23.08%), Coral (23.08%), Blubber (7.69%) or Shark Fin (7.69%). If it has not already been obtained and Woodlegs is not unlocked, there is also a chance that the chest will contain the Golden Key (10.00%).
For each Trinket the chest will only contain a certain number of Dubloons. Trinket values are as follows:
- His name is a portmanteau of "Yarr" (a pirate's phrase) and "octopus".
- It may happen that a Coral spawns right on top of the Yaarctopus. This doesn't hinder the player to turn in fish but can affect the spawning of the Octopus Chest.