#AtoZchallenge— H is for —Hold the Door!

From the Shadow Lands of Asshai to the Shores of Dragonstone and the frozen lands beyond the Wall comes the 10th anniversary of the AtoZ challenge...

“Hold the door, hold the door, hol’ the door, hol’ the door, ho’ the door, ho’ the door, ho’ door, ho’ door, Hodor, Hodor!” 

Hodor

Hodor's real name is Wylis. He is a gentle giant, the great-grandson of Old Nan. When he was young he experienced 'Bran-Starks-greensight' gone wrong and warged into his grown-up body via Bran's past vision and all's he could hear was Meera telling him to "Hold the door"! After that moment, he could not speak again but that one word for the rest of his life.

Just FYI, a Warg is a person with the ability to enter the minds of animals and perceive the world through their senses and even control their actions. The act of doing this is called "warging." - source. For example, Orell, one of the Free Folk beyond the wall, could commune with his eagle.

Bran is also a greenseer and future 3-eyed-raven. He warged into Hodor frequently just to be able to experience things he could do and see without having to crawl. He entered his direwolf, Summer, as well.

Can you guess who the letter is?

He is known throughout Westeros as "The Hound" and was a member of the Kingsguard until he abandoned king Joffrey and his post at the fire of the Blackwater. The Hound is considered one of the most dangerous fighters in Westeros. As a child, he received gruesome facial burns when Gregor shoved his face into a brazier. He came to loathe fire, his brother, and the hypocrisy of knighthood in general.