Richmond worked at Naughty Dog since 2008 and his previous work included the multiplayer for Uncharted 2: Among Thieves and Uncharted 3: Drake's Deception.
A reason for his departure may be him joining the developers Riot Games, who are known for their League of Legends game.
Richmond left a statement saying:
"I have in fact made the decision to leave Naughty Dog. I love the company and the people and know that they will continue to create awesome games going forward. On a happier note, after careful consideration and exploration I have joined Riot Games. There is some really innovative stuff going on here that I can't wait to be a part of."
This news has sparked some concerns among fans, considering that Creative Director Amy Hennig left Naughty Dog not too long ago.
Hennig and Richmond were both credited for their involvement in the Uncharted series last year when the next-gen was revealed.
It looks like Sony has been having some issues lately, they have been restructuring their company by laying off employees and hiring job recruiters.
Keep checking back for more information on Uncharted 4.
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