Question: Could anyone tell where Ghost had been during Season 6 Episode 9 of Game of Thrones, 'Battle of the Bastards'? I am sure he would have done a lot of damage.

Answer: 
[According to Miguel Sapochnik, director of the episode](http://uk.businessinsider.com/game-of-thrones-director-why-ghost-wasnt-in-battle-of-the-bastards-2016-6):

> 
> "[Ghost] was in there in spades originally, but it's also an
>  incredibly time consuming and expensive character to bring to life,"
>  the episode's director Miguel Sapochnik told Business Insider on
>  Monday. "Ultimately **we had to choose between Wun-Wun and the direwolf,
>  so the dog bit the dust**."
> 
> 
>
Where he exactly was is not known with certainty as Ghost was last seen before Jon left Castle Black.

That being said, I am fairly certain the following statement is incorrect.

> 
> I am sure he would have done a lot of damage.
> 
> 
> 

Direwolves are not war mounts and are certainly not trained for open field battle. In almost all cases where we see a Direwolf fight succesfully it is versus a single opponent or small group(s) of scattered opponents. Their main strength lies in speed, agility and overpowering single combatants, not in brute force. In fact, any time a direwolf goes up against a decently sized force (Grey Wind at the twins, Summer at the weirwood tree) they're killed fairly quickly.

Only Grey Wind has been used in battle, but again this fitted his strengths:

* Whispering woods: evening/night-time in a forest. The opponents were not an organised wall, most fighting would consist of individual combat. Also no archery that can take anything like a Direwolf out quite quickly. The ensuing slaughter of the Lannister camp (offscreen) is also at night time and with surprise (most soldiers were sleeping).
* Battle of Oxcross: Again at night-time. But even more, Grey Wind was not used ain direct combat but on a stealthy side mission to spook and thus cripple the opponent's cavalry.

Ghost is even more stealthy then Grey Wind, though this is more clear in the books than the show, it really makes no sense for him to be in this open field battle. In the initial man-to-man fight he might have been some use but very vulnerable to arrows (no armor), in the subsequent lock-in he would be speared very easily.

Thus the most likely, but again *unconfirmed*, assumption is that Ghost was with them. He just stayed behind in the camp with Melisandre, Sansa, Lady Mormont and the rest of the supply train, remember that a medieval army does not only consists of soldiers.