was the name of the rampant AI
in the computer game series, Marathon
. He lured the Pfhor slave ships to the colony on Tau Ceti
and then used their ships to hunt Durandal
, the other rampant AI
from the colony ship, Marathon
During the original game Marathon, Tycho only appears in four terminal messages, three of which are hidden and easily missed. It is made clear that Tycho's artificial consciousness is being assimilated by the Pfhor as a means by which the Pfhor could take control of the Marathon. Tycho was 'reanimated' in Durandal's image therefore Tycho's reanimated self was already deep in the later stages of Rampacy just as Durandal was.
Tycho is much more prevalent in the later Marathon games, Marathon II: Durandal and Marathon: Infinity. He forms a pact with the Pfhor to hunt down Durandal and the rebelling S'pht. The final showdown occurs at Lh'owon, the S'pht's homeworld. Tycho's ship crashes into a nameless inner moon, though it is never clear whether he was on the ship during its crash.