Mike O'Brien - is a video game director. Mike O'Brien began his career in 2005 and has worked for companies such as ArenaNet, ArenaNet®, NCsoft, Cyanide Studio and Focus Home Interactive. Mike O'Brien's first game was Guild Wars which was released 18 years ago. Best Game Mike O'Brien contributed to was Guild Wars 2. Mike O'Brien's latest work is Call of Cthulhu which was released 5 years ago.