Mouseferatu
Hero
Rasputin's alleged mesmeric powers and great knowledge, as well as the great difficulties involved in killing him, were because he was, in fact, a regeneration of the Time Lord Mortimus, aka "The Meddling Monk." Discuss.
Where was he named Mortimus? Is that from the novels or something?
It's a cool idea for an episode! I'm not sure they should bring him back, though - the Master was enough, but the whole idea of the Time Lords being gone gets weaker and weaker when you start to realise it's "all the Time Lords except any you might have heard of..."
Haven't read the novels, but my (admittledly distant) memory of his appearances in the series (all very early), the Meddling Monk is fairly comic, almost well-meaning.
That would be difficult to reconcile with him being Rasputin.