Contra 4[a][1][2] is a 2D action game published by Konami Digital Entertainment in the United States and developed by WayForward Technologies.

Following the defeat of Red Falcon, a new entity called "Black Viper" begins launching attacks against the human race.

[5] Bill Rizer and Lance Bean are joined by Mad Dog and Scorpion as they travel to the fictional Galuga archipelago near New Zealand (the setting of the original arcade version of Contra[6]) on a "final" strike mission.

In the North American versions, Black Viper was originally the name of the main antagonist in Operation C, while "Mad Dog" and "Scorpion" were the codenames of Bill and Lance.

Other than using both screens, Contra 4 makes no usage of the DS' special features such as the touchscreen (besides navigating the main menu), microphone, or multiplayer modes.

The standard Jungle theme is actually an enhanced version of a "Contra style" chiptune song previously posted on Kaufman's website, called "Vile Red Falcon.

"[10][11] A soundtrack CD was announced by Konami to be bundled in the first print of the Japanese release of Contra: Dual Spirits, as a gift for preorders through the KonamiStyle shop.

In addition to the music found in the game, a 4-minute live performance of the "Harbor" song is included as a bonus track.

"[28] However, Edge gave it six out of ten, saying, "Is there any need, on vertically scrolling levels, for your character to die when they touch the bottom of the screen, despite the fact you know there are platforms there?