Iban is an evil non-player character who follows Zamorak. He is found deep in the Zamorakian Temple within the Underground Pass. Both the Iban Disciples and Iban staff are named for him.
During the Underground Pass quest the ritual that was used to resurrect him must be reversed in order to destroy him. This is done by combining four elements of him (Iban's flesh, Iban's blood, Iban's shadow and Iban's conscience) and throwing them into the Pit of the Damned.
According to Old Journal written by Kardia the Witch, he was a well known and profoundly wicked Black Knight who had died in a battle but was later resurrected by Kardia. It also describes him as being a merciless slaughterer and for having a taste "for the finer things in life". He is also said to have been well educated, with ambition that led him to "hungered for something beyond the mortal realm". He was known to seek allegiance from those around him, and enjoyed twisting everybody into a corrupt force of evil people. His ultimate ambition was to assemble a horde of soulless and evil people, but failed due to being killed in the "White Knight's now famous Dawn Ascent".
See Old Journal for the text that appears in game. See Rock for more writings on Iban, which can be found on rocks in the Underground Pass.