Whereas 'Game of Thrones' saw fit to release its mammoth cast and character list at Comic-Con last year, season 4 has taken a much more measured approach to revealing its new additions. Case in point, 'Sherlock' star and producer Mark Gatiss was announced for an upcoming role back in mid-July, but only now have details of the actor's role in season 4 come to light. So which of George R.R. Martin's characters will Gatiss bring to light?

According to Winter Is Coming, Gatiss will take the role of Tycho Nestoris, a representative of the Iron Bank of Braavos to whom the Iron Throne remains very much in debt, something Tyrion learned of last season in becoming the new Master of Coin. Curiously, Tycho doesn't appear within the 'Game of Thrones' narrative until sometime in George R.R. Martin's fifth book, 'A Dance With Dragons,' while HBO's adaptation continues moving through book 3, "A Storm of Swords," with a few elements from book 4, "A Feast for Crows," thrown in.

While we wait for ‘Game of Thrones’ season 4, HBO has cast in known roles Roger Ashton-Griffiths as Mace Tyrell, and Indira Varma as Oberyn’s lover Ellaria Sand. ‘Banshee‘ star Joseph Gatt will appear in a role speculated to be that of Wildling chieftan Styr, Magnar of Thenn, while 'Treme''s Michiel Huisman will replace Ed Skrein as Daario Naharis, and Hafthor Julius Bjornsson will take over the role of Gregor “The Mountain” Clegane from Ian Whyte, among other recastings. Previous season characters Lysa Arryn (Kate Dickie), Ser Alliser Thorne (Owen Teale), Rorge (Andy Beckwith) and Janos Slynt (Dominic Carter) will likely all return, among others.

Well, what say you? What does HBO's 'Game of Thrones' have to gain by introducing Mark Gatiss as Tycho Nestoris earlier than expected? Give us your predictions in the comments, while we wait for season 4 in 2014!

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