Natalia played the role of the one Nymphadora Tonks in Harry Potter who, of course, went on to have Teddy with Remus Lupin. She also appeared as Osha — who traveled with and watched over Rickon Stark — in Game of Thrones.
2.Michelle Fairley
Warner Bros., HBO
Michelle made a very quick appearance as Hermione Granger's mother in Harry Potter and the Deathly Hallows (Part I). However, Game of Thrones fans might recall her memorable role as Catelyn Stark.
3.David Bradley
Warner Bros., HBO
David played the role of the one and only Hogwarts caretaker Argus Filch in Harry Potter. In a slightly similar fashion, he portrayed the wicked Walder Frey — head of House Frey — in Game of Thrones.
4.Ciaran Hinds
Warner Bros., HBO
Ciaran portrayed Albus Dumbledore's brother, Aberforth Dumbledore, in Harry Potter and the Deathly Hallows (Part II). He also appeared as "King-Beyond-the-Wall" Mance Rayder in Game of Thrones.
5.Freddie Stroma
Freddie appeared as a fellow Gryffindor and Quidditch master Cormac McLaggen in Harry Potter. He also graced our screens as Samwell Tarly's younger brother Dickon in Game of Thrones.
6.Jim Broadbent
Warner Bros., HBO
Jim appeared in Harry Potter and the Half-Blood Prince as Professor Slughorn, known for openly choosing favorite students for his Slug Club. He also played Archmaester Ebrose — the one who told Sam he shouldn't try to cure Ser Jorah's greyscale — in Game of Thrones.
7.Ralph Ineson
Warner Bros., HBO
Ralph played the evil Amycus Carrow in Harry Potter. He also portrayed Dagmer in Game of Thrones (he helped Theon Greyjoy take Winterfell).
8.Julian Glover
Warner Bros., HBO
Julian voiced the enormous spidered named Aragog in Harry Potter and appeared as Grand Maester Pycelle in Game of Thrones.
9.Bronson Webb
Warner Bros., HBO
Bronson had a small role in Harry Potter playing Pike, a Slytherin friend of Draco Malfoy. He also was one of the very first deaths in Game of Thrones when he portrayed Will, the Night's Watch ranger.
10.Nicholas Blane
Warner Bros., HBO
Nicolas had a blink-and-you-miss-it role in Harry Potter as Bob, a wizard at the Ministry of Magic. He also appeared in Game of Thrones as the Spice King.
11.Sally Mortemore
Warner Bros., HBO
Sally portrayed the Hogwarts's librarian Madame Irma Pince in Harry Potter as well as a Braavosi woman on Game of Thrones.