Hyperion Cantos Wiki
"A lesser light asks Ummon, What are the activites of a sramana? Ummon answers, I have not the slightest idea. The dim light than says, Why haven't you any idea? Ummon replies, I just want to keep my no-idea."
―Ummon to Brawne Lamia and Johnny[src]

Ummon is an AI of the TechnoCore.

Ummon derives his name from the ancient Chinese Zen master Yunmen Wenyan, whose name is translated as Ummon in Japanese. Like his namesake, Ummon has a fondness for speaking in koans, using them to illustrate concepts when communicating with lesser intelligences. He also frequently uses the exclamation "kwatz!" as an expression of humor; this is another element taken from Zen teachings.

Ummon's fate remains uncertain. It is possible he was destroyed shortly before the fall of the Hegemony, dismantled by other AIs during the civil conflict within the TechnoCore.