Diemer announced his appointment on Twitter, stating "Robosaurs! @Guerrilla! And me! I'm very excited." The developer has yet to announce what position he'll be taking on, but given his reference to robosaurs, expect him to play a significant role in next year's Horizon: Zero Dawn.

According to his LinkedIn profile, Diemer worked at Dead Island 2 developer Yager for almost 4 years, having joined the company in January 2012. He left earlier this month. Before then he served as a producer and design director at Crytek.

Yager was pulled off of Dead Island 2 by publisher Deep Silver earlier this year after the two companies' "respective visions of the project fell out of alignment". A new developer for the game has yet to be announced.

Source: @bernddiemer