Mechanized Attack is a game where the player uses a machine gun to stage an assault on a tropical island that's home to a cyborg army. Battle through numerous stages beginning with an approach to the island. This first stage is held over the water and features at attack on a number of small gunboats, a helicopter, and an entire battleship. As the player progresses through the stages of the island, the human (and even canine) enemies are revealed to be robots when the flesh is destroyed. At various junctures of the game, the player is allowed to choose which game path to pursue.

In the NES version, the player can use either a gamepad or the NES Light Zapper to carry out the mission. While the arcade version of Mechanized Attack has a miniature machine gun replica for the player to use, the NES version attempts to reproduce the feel by allowing the player to hold down a game pad button or the Light Zapper trigger for automatic fire. Extra ammo is plentiful so be sure to fire at those power-up boxes to grab as much as you can. There are also more powerful grenades which are in much shorter supply than the bullets.