Contra 4 for the Nintendo DS is a direct sequel to 1994 SNES Contra III: Alien Wars. Two years after the defeat of Red Falcon - the first wave of the alien colonization fleet, the main invading force Black Viper approaches Earth. The heroes of the original Contra series - Billy Rizer and Lance Bean as well as two newcomers - Mad Dog and Scorpion are now humanity's last line of defense against total annihilation.
This installment of the long-running series adds dual screen gameplay, enabling the player a wider view, and a 2-player co-op mode via local Wi-Fi connection. Each player is now given two weapon slots which can be filled with any one of the game's many weapon power-ups and switched at will with a press of a shoulder button. The game features nine levels set in such classic Contra locations as Jungle, Waterfall and a pseudo-3D Base.
As a bonus, the cartridge contains an illustrated history of Contra, as well as the Contra and Super C original NES games.