Released on February 28, 1992 in Japan for 8500 Yen.
Contra Spirits was developed by Konami with a team led by Nobuya Nakazato. Although this was Nakazato's third year at Konami, Contra Spirits is the first Contra game he worked on, having only previously done informal playtesting for Super C (1990). He believed the original arcade version of Contra (1987) was difficult to play because of its vertical screen, but he did enjoy the Famicom port. Nakazato's team worked in Konami's new offices in Tokyo, seated next to the arcade team that had developed Contra. Nakazato shared progress on Contra Spirits with the arcade team and received positive feedback. In early coverage, the game was known as Super Contra IV. Nintendo Power reported the name change to Contra Spirits in its coverage of Winter CES in 1992.
Nakazato believed Contra had a low-budget movie theme. To emphasize this, he asked the sound team to change the music as the stages progressed to give a cinematic style. He also believed the action in earlier Contra games is too realistic, so for Contra spirits he wanted to include more comical elements. He was concerned the change may upset series fans, but believed it would be more entertaining. One scene added to accomplish this is a sequence where the player hangs from flying missiles. This strains the Super Famicom's sprite capabilities, so the team used background tiles to draw the helicopter and missiles in the scene. Making the graphics appear to move like sprites in the foreground required clever programming tricks. The Super Famicom allowed for raster scrolling, which allowed the programmers to change the graphics for each scanline. The programmers shifted the vertical sync and cut off the sprites at the scanline. The restriction is that graphics can only move horizontally along the scanline to achieve the illusion that they are actually sprites in the foreground.
Nakazato was concerned the traditional pattern of weak enemies followed by a boss fight was becoming mundane and did not want players to feel "in for the long haul" every play session. To combat this, he established a key concept for something interesting to happen every three screen scrolls. This made the game content feel more dense and gave it a boss-rush type feel. Nakazato believed Contra Spirits's fast-paced action was going against the trend of home console games shifting to slow-paced strategy and role-playing games, and is good for quick-starting stress relief.
[FR] May 1992 - Joypad N.8 (Page 132-135): 95/100
[US] "Contra III - The Alien Wars [Model SNS-CS-USA]
[EU] "Super Probotector - Alien Rebels [Model SNSP-CS-NOE]