Mord is a character in Game of Thrones. He is played by Ciaran Birmingham and appears in the first season.
Mord is the turnkey in charge of the sky cells in the Eyrie. He is in the service of House Arryn. He does not have a particularly advanced intellect.
Season 1
The Wolf and the Lion
Mord beats Tyrion
Tyrion Lannister is given into Mord's redoubtable care whilst a prisoner at the Eyrie.
A Golden Crown
With great difficulty, Tyrion manages to bargain with Mord to allow him a fair hearing, under the promise "a Lannister always pays his debts".
In the books
In the Song of Ice and Fire novels, Mord is a petty, slightly cruel man who delights in tormenting prisoners and telling them how they are going to fall out of the cells to their deaths on the rocks thousands of feet below the castle.