Contra - an 8-bit run-and-gun action platformer, notorious for its high difficulty.
The player character comes armed with a gun that can shoot infinitely.
There are a total of eight stages in the game. A boss can be found at the end of each one, which has to be defeated in order to proceed to the next one.
Collect the Eagles to change the gun power, and kill the robots and to get escape from them. Finally manage to kill the boss to win the game.