Hatius Cosaintus is located just outside of the Lumbridge Castle. He awards players the Explorer's ring for completing easy, medium, hard and elite tasks of the Lumbridge Diary.
- His name is a pun based on the phrase, "Hate us cause they ain't us", due to the fact he is wearing very rare and highly coveted equipment.
- His out of place and unrealistic appearance has been criticized by players which led to the proposal to have him removed in Poll #50. However, with only 56.1% voting 'Yes' it didn't pass.