Celebrated arcade game designer and programmer Tim Skelly has passed away. 

Seamus Blackley, a friend and colleague of Skelly, shared the news on Twitter and highlighted some of his notable contributions to the games industry, which include creating the first 3D arcade fighter, pioneering co-op play, and designing a respawn system. 

During the '70s and '80s Skelly designed a number of influential vector arcade titles for Cinematronics including Rip-Off, Star Hawk, Armor Attack, and Star Castle, all of which were eventually ported to the Vectrex home console. 

After his stint at Cinematronics he had spells at Gremlin and Gottlieb, where he created the raster arcade game Reactor, which was the first coin-op cabinet to credit its creator on the in-game title screen. He also designed two other titles for Gottlieb called Insector and Screw Loose, although they never saw the light of day.