Sycorax The Sycorax were a superstitious race of warriors and intergalactic plunderers . The Seventh Doctor considered the Sycorax to be " snarling space gangsters who smell like herrings and that ' s on a good day " . ( AUDIO : " Harvest of the Sycorax " ) Biology . The Sycorax had both an endo - and exoskeleton . The latter covered part of their head ( giving them a skull - like appearance ) , leaving the rest of their skinless faces exposed to the elements . The exoskeleton could vary from a smooth , skull - like shape ( TV : " The Christmas Invasion " ) to a more jagged , horned shape . Some had long flowing hair . ( COMIC : " The Widow ' s Curse " ) The Sycorax also mounted horse - like creatures with the same biological facts , suggesting that they were related . ( COMIC : " The Widow ' s Curse " ) Culture . Sycorax men wore the ribs of their wives as a marriage bond . ( COMIC : " The Widow ' s Curse " ) The native language of the Sycorax was Sycoraxic , and in this language , the words for ' argument ' and ' fight ' were the same word . ( AUDIO : " Harvest of the Sycorax " ) The Sycorax practised slavery . They attempted to enslave humans in their Christmas Day invasion . ( TV : " The Christmas Invasion " ) The Sycorax ' s motto and battle cry was " Sycorax strong ! Sycorax mighty ! Sycorax rock ! " . ( TV : " The Christmas Invasion " ; AUDIO : " Harvest of the Sycorax " ) Religion . The Sycorax were a superstitious race who believed in magic and witch craft . ( TV : " The Christmas Invasion " ) They worshipped the god Astrophia . ( PROSE : " The Final Darkness " ) Some Sycorax worshipped in churches . ( COMIC : " The Widow ' s Curse " ) They also dedicated a huge room of their spaceships as a cathedral - like group worship chamber , regulated by a Sycorax priest . Within the chamber was a giant statue of Sycorax form , called a ' Wish of Bones ' , which was fashioned out of the skulls of the species that they had murdered and conquered . ( AUDIO : " Harvest of the Sycorax " ) Technology . The Sycorax could detect energy signatures , letting them identify advanced technology . ( TV : " The Christmas Invasion " , PROSE : " The Final Darkness " ) They also had devices which resembled sea mines called Foraxi Yox . They functioned as black box recorders for spacecraft , allowing later viewings of events . ( COMIC : " The Widow ' s Curse " ) The Sycorax used energy whips which could destroy all the flesh in a body , leaving only burnt bones . During the invasion of Earth , they also used blood control . They understood , but did not speak , Earth languages such as English as this would " dirty their tongues " . ( TV : " The Christmas Invasion " ) The Sycorax ship was , in fact , a hollowed - out meteor and contained rooms such as a main hall , a grand worship chamber and sleeping quarters . The ship itself used the molten core of the meteor as its fuel . ( AUDIO : " Harvest of the Sycorax " ) History . In 102 , the Sycorax were among the races who joined the Alliance . They came to Stonehenge and helped imprison the Eleventh Doctor in the Pandorica to " save " the universe . ( TV : " The Pandorica Opens " ) At Christmas 2006 , a Sycorax asteroid ship entered the Sol system . When the space probe " Guinevere One " crashed into them , they used the blood sample for blood control , threatening to kill every human with A + blood unless they were given half the population as slaves . The Tenth Doctor ( who had just regenerated ) and his allies Mickey and Rose were inside his TARDIS . The Sycorax picked up a signal from the TARDIS ' advanced technology and teleport ed them to their ship . The Doctor activated the blood control , knowing human survival instincts would break its hold . The Doctor challenged and defeated their leader in a sword duel , forcing the Sycorax to leave Earth and humanity alone . However , as the Sycorax ship was leaving Earth , Harriet Jones ordered Torchwood to fire at it with a salvaged alien ray weapon , from a Jathaa sunglider , destroying it . ( TV : " The Christmas Invasion " ) The wives of the Sycorax who invaded Earth came to the Sol system to find them , but found only the dust remains . They disguised their ship as an island called Shadow Cay , hypnotising all of humanity into believing it was discovered by Columbus . The Sycorax spent years searching for the ship ' s black box , the Foraxi Yox , and killed many humans , reanimating and controlling them as zombies , or human abstracts , to find it . In 2009 , after discovering from the Foraxi Yox recording that humanity had betrayed the Sycorax , this group of Sycorax had a 747 aeroplane boarded with phage abstracts Gilfane Craw had created take off , intending to spread a virus carried by the abstracts that would stop death but leave humans in agony for centuries . Donna Noble and Norah stowed away on the plane , and flew it back to Shadow Cay before it could reach London and spread the virus throughout humanity . Meanwhile , the Tenth Doctor overloaded the ship ' s magma - sculptor by making it attempt to copy the whole of Earth , and set its controls to take off before it exploded . ( COMIC : " The Widow ' s Curse " ) In 2010 , a Sycorax was seen at the Zaggit Zagoo bar when the Tenth Doctor came to visit Jack Harkness one last time before his regeneration . ( TV : " The End of Time " ) A Sycorax was present in the Maldovarium when Colony Sarff visited the establishment while searching for the Twelfth Doctor on behalf of Davros . ( TV : " The Magician ' s Apprentice " ) The Sycorax returned to Earth in the late 21st century with hostile intentions but returned home quickly . ( PROSE : " Snowglobe 7 " ) During the 41st century , the Astrophia Tribe died out during the Valhalla wars . The Tenth Doctor and Martha Jones met a lone survivor , a hunter collecting the last members of extinct species . ( COMIC : " Agent Provocateur " ) In the future of the Human Empire , the Sycorax entered a secret deal with Pharma Corps , a pharmaceutical company that had the blood of every human sealed away in its vaults . With Pharma Corps controlling the emotions of every human in the Empire , they were able to give the Sycorax access to the blood of ninety nine percent of the human race . Just as the Sycorax were finding the means to enter its vault , the Seventh Doctor and new accomplice Zanzibar Hashtag , were able to trick the Sycorax by using the blood of a dead Sycorax in a blood controller , thus placing the whole fleet into a state of hibernation . Whilst under control , all of the Sycorax fleet were teleported back onto their ship and sent away . ( AUDIO : " Harvest of the Sycorax " ) The Tenth Doctor told Martha that the Sycorax survived the end of the universe , along with human s and another unidentified species . ( COMIC : " Agent Provocateur " ) Alternate timeline . In an alternate timeline , the Sycorax tried to invade Mandorla . ( AUDIO : " Enemy Lines " ) Other references . In 1599 , the Tenth Doctor , in the presence of William Shakespeare , noted how an animal skull reminded him of a Sycorax , inspring the name of the mother of Caliban in Shakespeare ' s " The Tempest " . ( TV : " The Shakespeare Code " ) The Sycorax was one of the 11 creatures who appeared in the hologram projection shown by the Atraxi as they were scanning Earth ' s history to check if it was protected . ( TV : " The Eleventh Hour " ) The Great Intelligence mentioned , among others , the death of " the leader of the Sycorax " at the hands of the Doctor to dispute Madame Vastra ' s claim that the Doctor was never " blood - soaked " . ( TV : " The Name of the Doctor " ) Their destruction was also mentioned by a version of Kate Stewart during negotiations between UNIT and the Zygon s in the Black Archive . ( TV : " The Day of the Doctor " ) Sometime in 2010 , Mr Smith stated that his sensors were fully occupied by a Sycorax ship . He further mentioned that the Sycorax were not coming to Earth that day and there was nothing to worry about . ( WC : " " ) Behind the scenes . Russell T Davies ' original concept for the Shadow Proclamation scene in " The Stolen Earth " included an appearance by several Sycorax , but his plans to feature a " rogues gallery " of alien races in the scene fell through ; ultimately the Judoon were the only returning race featured . " The Visual Dictionary " . The source " " gave further information about the Sycorax . They could live up to four hundred years . The Sycorax were organised into the Sycorax empire , divided into large tribes . Sycorax had pride , honour , and some respect for the rules of war . Leadership was earned by trials of strength and combat . They wore skull - helmets to impress their enemies , and red - robes as a sign of leadership . They would take trophies of body parts such as bones , skin or hair from conquered races . Some wore belts of Judoon skin . Sycorax had many ancient rituals involving suns and moon s . They left a hole in their space - ships for the solar and lunar light to get in . Despite being spacefaring , many Sycorax relied on simple weapons , such as sword s and knives , generally adorned with trophies . The Sycorax used asteroid s fitted with an All Speed Inter - System Type K engine as spacecraft . The first of these asteroids was the home world of the Sycorax , the Fire Trap . At some point in Sycorax history , an alien spaceship crashed into the Fire Trap . They used its engines to turn their asteroid into a spaceship . More asteroids were added by other tribes , creating the Sycorax Armada . They used teleport ers to move to and from the ship . Many tribes left their home region in their asteroid ships to explore space , to conquer and enslave other planets , expanding the empire . The tribe that invaded Earth in 2006 was called the Halvinor tribe . " The Time Traveller ' s Almanac " . According to the source " The Time Traveller ' s Almanac " , they had the capability to translate the languages of other species .