"The Sycorax were here bcause something was going down. They're basically the biker gang from the beginning of season six of Buffy"

Ooh! Nice analysis. =:o}

And there was I thinking... 'Those bony heads of theirs look a bit familiar... and they use "blood control", which the Doctor hasn't seen "in years"... Possibly since his 8th incarnation?...'

Could they be some remnant of Faction Paradox, ignorant of their origins and their former powers? (Else they'd have reacted a bit more strongly to the phrase "Time Lord" and to seeing the Doctor's hand lost and regrown.)