Abadox is a shooter for the NES, which can be played by 2 people. It was published by Natsume.
Abadox is a commonly available game for the NES. It shouldn't be too difficult to find this game for purchase. In good condition, the game is worth about $3.00. Abadox was released on 12/15/1989. The save feature for Abadox is: No save feature.
Press A,A,Up,B,B,Down,A,B,Start at the title screen. You'll have to pause the game once playing to beome invincible.
At the title screen, press A,A,Up,B,B,Down,A,B,B,Start.
At the title screen, press Left, Up,Right,Down,Up,Right,Left,Down, and then your "level button". Up (level 2), Left (level 3), Down (level 4), Right (level 5), Select (level 6), B (level 7).