Biodata virus
A biodata virus was a virus that altered the biodata of its victim. One, created by Morlock, did so in such away that they became a member of Faction Paradox. (PROSE: The Book of the War) It could only infect a Gallifreyan if they were regenerating.
Mathara took this virus to Dust so she could infect I.M. Foreman during their regeneration. All did not go to plan, and the virus instead infected the Third Doctor after he was fatally wounded. (PROSE: Interference - Book Two)
Another was sent by the enemy to uncouple the Lucrecian Order from the Spiral Politic. It infected a member of the Faction Paradox team sent to the scene, Cousin Heyward, turning him into an enemy agent. (PROSE: The Complete History of Faction Paradox, Vol 1 [+]Loading...["The Complete History of Faction Paradox, Vol 1 (short story)"])
