Metal Slug 1st Mission

Metal Slug 1st Mission is a Neo Geo Pocket Color game that was released by SNK in Japan in 1999. It was available a second time for the Best Collection series on 2000.

Story
The following is a verbatim copy of the story on the Metal Slug Anniversary site:

The year is 2027 A.D.

In a land of continuing strife, illegal arm sales are occurring with disturbing frequency. Subsequent investigations reveal that the distributors of the weapons are not guerrillas but the Government Forces themselves. The distribution center for the weapons turns out to be more massive than estimated, and it is clandestinely manufacturing new weapons which even include the top-secret SV-000 "METAL SLUG" prototype currently in development. The commander of the squad protecting this region turns out to be the expert at guerrilla warfare Colonel Hilde Garn, and his aide-de-camp turns out to be the master at hand-to-hand combat Lt. Colonel Macba, who stood on the front lines himself and struck terror in the hearts of the enemy. If this squad led by Hilde Garn, which is praised as the mightiest in the army, is the force behind the illegal weapon sales, it was feared that this could lead to a coup d'etat. The Intelligence Agency of the Government Forces, taking a particular grave view of the situation, decides to enlist the services of the ultra-elite Special Forces Squad Peregrine Falcons.

The mission is given: infiltrate the materiel distribution center, destroy it, and capture the villains.

You are the cadet who volunteers to join this squad. Do you have what it takes to accomplish this punishing mission…?

Gameplay
Metal Slug 1st Mission plays similarly to other Metal Slug games, but has toned down graphics for the Neo Geo Pocket Color hardware. Notably, grenades are thrown by pressing the option button to switch, then fire. This was changed in the sequel. When the game is completed once, another character becomes playable. There are five different difficulty levels: kids, easy, normal, hard, and very hard.

Characters

 * Hero (A.K.A. Marco Rossi) - a cadet who volunteered to take part in the operation as a member of the Peregrine Falcons.
 * Lieutenant Colonel MacBa - a fearsome brawler who can conceal his presence through a special suit.
 * Colonel Hilde Garn - key target and a guerrilla expert. He is the ringleader of his private development of new weapons.