Raptor: Call of the Shadows

Raptor: Call of the Shadows is a vertical scrolling shoot 'em up developed by Cygnus Studios (now known as ) and released early 1994, several months after the first release of Doom.

The game has some loose technical connections to Doom: Doom's setup program appears to have been derived from the setup program written for Raptor. Early versions of the setup tool included copyright attribution to Cygnus Studios at the top of the screen.

Raptor is also notable for being the only known game not using the Doom engine to have used the DMX sound library developed by Paul Radek.

Apogee and Cygnus Studios previosly licensed the Raven engine from id in 1992. In 1993 id Software and Cygnus Studios made a deal to create a game based on the Doom engine and Cygnus Studios was relocated to an office next to id.

Sandy Petersen reviewed the game positively in  issue #208.

Updated versions of the game are still being sold today.

Trivia

 * Some of Raptor's assets are reused in Strife: Quest for the Sigil. Rogue Entertainment was founded by disgruntled employees of Cygnus who left the company when its founder, Scott Host, intended to move the company to Chicago and cancel the Strife project.
 * A piece of artwork related to the game was included in the 2015 Doom source data release.