He appears during Awash World Change
Legend:
The remains of a sunken dynasty unkown can now be accessed beneath Kazordoon.
To activate the World Change
A new steamship travels between Kazordoon and Thais, but the path is flooded at Sunken Mines, near Kazordoon. Special pumps have been brought in to drain the water, but they need coal to operate. Apparently the remains of a sunken dynasty of unknown age is covered under the water and can be accessed when there is enough coal to drain the area.
Bring 200 nuggets of coal to Dronk and use them on any of the three Water Pumps down the mines. Once enough coal have been used, the pumos will start working by themselves, which means the mines will be opened at the next server save.
The day after there is enough coal the entrance will be revealed and you can enter a dungeon populated by Deepling Scouts and access the steamship. This steamship is different than that found inside of Kazordooon, it can bring you to Thais, Kazordoon (the tradisional steamship) or Robson's Isle.
Anwsering you question: He Spawn Everytime as SS plus 1 or 2 hours. this are the times I find the boss.
hope this help you.