Shayde Shayde was an instrument of the Matrix Lord s placed on the TARDIS against the Doctor ' s will and without his knowledge . In time , the Doctor ' s fifth self — and later his eighth incarnation — found a way to work with Shayde , despite the fact that Shayde was ultimately working for various Gallifrey an interests . As a construct rather than a fully organic being , Shayde had the ability to both emulate and actually join with other beings . His adventures with the Doctor occurred with him in one of three main identities . The " default " , unitary Shayde that the Doctor ' s fifth self exclusively knew was followed by a Shayde who pretended to be a new incarnation of the Doctor . Shayde then joined with Fey Truscott - Sade to become " Feyde " . Biography . As Shayde . Origins . Shayde had his origins in the Matrix , where the minds of the physically dead Time Lord s who resided there created him . He was a servant of Rassilon . An earlier , female construct , the Pariah , preceded Shayde . The Pariah was another construct of Rassilon , but he tried to destroy her when she developed free will and rebelled against him , massacring a few thousand Time Lords . The Pariah survived the ensuing conflict , landing in 1879 Arkansas , where she merged with a human and created the first of the Threshold . ( COMIC : " Wormwood " ) Encounters with the Doctor . The Doctor first met Shayde when he appeared to help him defeat Melanicus , at first covertly but then , as the Time Lords increased his power levels and he was able to manifest himself , directly . ( COMIC : " The Tides of Time " ) He aided the the Fifth Doctor against another force , a mutated Gallifrey an creature called a rovie that had infiltrated the Doctor ' s TARDIS and was trying to kill the Doctor and his companion s Peri and Erimem . ( AUDIO : " No Place Like Home " ) Shayde encountered the Doctor again during his eighth incarnation and near following the events of a recent adventure . ( COMIC : " Tooth and Claw " ) His companion s at the time , Izzy and Fey , had taken him back to Gallifrey , where he was cured and his mind placed within the Matrix to recover . While in the Matrix , an attempt was made on the Doctor ' s life by a secret Time Lord sect known as the Elysian s , which Shayde prevented . The assassination attempt was part of a plot by Overseer Luther , an insane Time Lord who wanted to rewrite Gallifrey ' s history and set himself up as a god . The Doctor thwarted Luther by short - circuiting his watchtower ( a gigantic TARDIS ) , but apparently at the cost of his life . As Izzy and Fey watched , the Doctor , actually Shayde , apparently regenerated into a new incarnation . ( COMIC : " The Final Chapter " ) As the Doctor . The Doctor ' s " regeneration " was a ruse . The Doctor had realised that Fey was under external control when she had managed to pilot the TARDIS even though the TARDIS manual was in Gallifreyan script , which she did not understand . Just before the Doctor sacrificed himself , Shayde offered to take his place and fake a regeneration . The Threshold , now a mercenary organisation that the Doctor had already tangled with , would seize the opportunity to bring a newly regenerated and thus weaker Doctor to them . Shayde would hold their attention while the Doctor , disguised with a personal chameleon circuit , covertly sabotaged the Threshold ' s operations . The TARDIS landed in Wormwood , a Threshold stronghold which resembled a town on the Moon . When Shayde and the Doctor revealed themselves to the Threshold , Shayde had to contend with the Pariah , who wanted revenge , not just on Gallifrey but the whole universe . Shayde was unable to defeat the Pariah on his own and so crushed the globe forming his head . Fey merged with the dying Shayde and together they killed the Pariah and defeated the Threshold . The shared being , dubbed " Feyde " by the Doctor , although both of them retained their own consciousness , decided to leave and deal with what had just happened to them . ( COMIC : " Wormwood " ) As Feyde . Fey returned to her own time period , the 1940s , where as an agent of the British government , she spent two years fighting the Nazi s . Shayde would not allow her to use their powers to kill Adolf Hitler , as this would change history , this has caused the two to form a love / hate relationship , complimenting each other whilst resenting aspects of their flaws . In 1941 , she received a sub - ether summons from the Doctor — Izzy had been kidnapped , and the Doctor needed Shayde ' s abilities to track her whereabouts . ( COMIC : " Me and My Shadow " ) Together , they succeeded in recovering Izzy . " Feyde " returned to World War II . ( COMIC : " Oblivion " ) Powers . Among Shayde ' s many powers were the abilities to travel through space and time and , via a sleek pistol that he carried , fire deadly , self - generated psychic bullet s . He could also make himself invisible to security systems , phase through solid objects , and , given enough data , accurately track people through time and space . Additionally , he could , at least in his original form , remove his spherical " head " and store things in his " body " via the resulting , apparently dimensionally transcendental , gap . ( AUDIO : " No Place Like Home " ) Behind the scenes . In the comic story " Old Girl " , the Tenth Doctor encounters a species of Time Sentinel s living on Gallifrey . He notes that he has " seen something like this before . " This is most likely meant to be a reference to Shayde , who looks identical to the Sentinels . " The Good Companion " makes a reference to Aspect Black , who operated alone , in a similar manner to the Doctor .