FIRST, THE BEGINNING
The Metal Slug series of games (”Metal Slug," ”Metal Slug 2,” and ”Metal Slug X”) is an all-out shooting game crafted by game artisans who dare to battle against the competition in this age of 3D games with intricate 2D graphics! The gist of the game is this: a battle breaks out between the Government Army and rebels led by General Morden, and all the action occurs in the conflict known as ”Morden’s Battle.” But what enemy awaits our heroes in ”Metal Slug 3"...? Here's the lowdown:

SETTING OF "METAL SLUG 3"
Thanks to the superhuman efforts of Marco and Tarma, as well as Eri and Fio, the second coup d'etat pf General Morden who advocated the "construction of a New World Order" has been defeated. Contrary to their wishes after this battle, Major Marco and Captain Tarma, who were instrumental in crushing Morden’s army, were ordered to assume leadership of the Peregrine Falcons Squad (abbreviated as PF Squad) after their requests for discharge were ignored. The abilities of these two are still deemed necessary to wipe out the remnants of Morden’s army scattered throughout the world.

Morden’s Battle 2 What is MCC2 (Mission to Crush Coup Two)...?
It’s the name of the previous mission to crush the second rebellion led by General Morden. Given its secrecy, the general public knew nothing of it. Even after it ended successfully, the Government Army refused to reveal it. Reasons for this action remain unclear. Rumour has it that the secrets behind it are too shocking, but conspiracy theorists surmise that Morden, said to have ”died accidentally," is quite alive and well.

The Peregrine Falcons Squad
Without seriously examining the causes behind the coups, the Government Army, apparently learning nothing from the Morden War that stretched over two conflicts, ignorantly devotes itself to hunting down the rebel remnants and employs a ”policy of force” that is no different than that of the past. Those instrumental in hunting down these remnants are the heroes of the big war, the Peregrine Falcons Squad (PF Squad). The public who believes undoubtedly that the ”antichrist" Morden was solely responsible for the coup and heaps lavish support on FF Squad to eradicate Morden’s forces. However, there tends to be resentment mixed with jealousy toward PF Squad among some soldiers who sense the corruption of the Government Army. Marco, raging with hate against Morden, fails to see this, while Tarma has the feeling that the military is not being all it can be.

Sparrows
It may be a result of poor PR skills, but the appraisal of SPARROWS remains low in spite of their activities during the big war. Perhaps it's because Marco and Tarma are so famous, but it's probably due more to the closed nature of the Intelligence Agency. Stated more bluntly, SPARROWS are an object of contempt among the Government Army's upper echelons.

Details Leading to the Investigation of Mysterious Incidents
In spite of the existence of numerous witnesses, testimony, and proof that suggested the existence of "alien intelligence" during the two big battles of the Morden War, the upper echelons of the Government Army ignored these as ”wild flights of fancy" and the ”products of mass panic in extreme situations.” Apparently only the Intelligence Agency seriously pursued the facts; however, this caused a wider rift the between powers that be and that affects the current situation.

ASIDE: THe Promotions of Eri and Fio
The mission to crush Morden’s second coup was top secret. Consequently, the military put off all showy promotions, but noncommissioned officers whose achievements were remarkable proved exceptions to this rule, and Eri was promoted from a sergeant to a sergeant second-class, while Fio went from a sergeant first-class to a sergeant-major. Aside from those like Eri, it was the posture of the Intelligence Agency to overuse the promotion process for those with the level of achievements of Fio. But the upper echelons of the Government Army derided and ignored them, since they did not attach any importance to SPARROWS in the first place. For reasons unknown, Fio subsequently shot up from the rank of sergeant-major to senior sergeant—major, practically receiving a special promotion of two ranks....