Bruce Straley is leaving Naughty Dog after 18 years with the studio.

Notably, Straley was director on The Last of Us, Uncharted 2: Among Thieves, and Uncharted 4: A Thief's End.

He called his decision to leave his "home" of Naughty Dog the hardest of his career.

"After heading up three extremely demanding projects, and taking some extended time away from the office, I found my energy focusing in other directions, and I slowly realized this was the signal that it’s time to move on," Straley wrote in a blog post.

"I'm leaving Naughty Dog with the strongest team it's ever had, and that's saying a lot.

"But more than the talent, it's the people that I'll miss the most. The work culture at Naughty Dog is about getting out of your seat and solving problems together," he added.

"It's what has allowed me to build so many friendships and gain so much respect for this stellar group of people."

Straley joined Naughty Dog in 1999 as a texture artist on Crash Team Racing, before becoming a creative lead at the studio.

He thanked both Naughty Dog staff and fans of its games.

"Knowing I was a part of creating something that touched or moved any of you made this whole thing worthwhile, and now I, too, get to anticipate the next Naughty Dog masterpiece!" he wrote.

"As I close this chapter with a heavy heart and an appreciation for everything Naughty Dog has done for me, I open the next with an excitement to continue the journey into the creative process.

"I don’t have anything to announce just yet, but I look forward to the discovery and to sharing it with you all soon."

Naughty Dog creative director Neil Druckmann, who often worked closely with Straley, tweeted, "Bruce Straley has been my mentor, directing partner, & friend. I miss working with him but am excited to experience whatever he does next."