Metal Slug X is an enhanced version of Metal Slug 2: Super Vehicle - 001/II . The main differences to the original release include: Additional weapons: Stones, Iron Lizard, Enemy Chaser, Super Grenade, and Drop Shot. Additional power-ups, items, and prisoners in most of the levels. Stages can take place at twilight, sunset, or dusk. Some of the locations and vehicles in the game have been altered. Increased enemy count. Some of the enemies' placement has been changed. Many weapons have a stronger explosive force. Explosions yield more unexpected results. The soundtrack has been re-mixed.
The story follows the same plot as before, with a team of special forces fighting against an evil organization known as the Black Wings.
Gameplay involves co-op action and adventure elements, where players control a team of soldiers as they fight their way through levels to take down enemy bases. The game features fast-paced action, platforming, and a variety of weapons to use against enemies.
Metal Slug was released on August 7th, 1997 for the PlayStation console.