The Clones are, as their name suggests, imperfect clones of the original Peregrine Falcon and S.P.A.R.R.O.W.S soldiers. These grotesque aberrations of nature are created by the Mars People. They serve as the final regular enemies of Metal Slug 3.
In Metal Slug 3, after the General Morden on the Hi-Do is revealed to be an imposter, the Mars People kidnap Player 1's character and take them and the real General Morden deep into the Rugname. A substitute character is sent via Astro Slug to infiltrate the Rugname to rescue the kidnapped soldier alongside the Rebels.
After destroying Rootmars' control center (which causes the Rugname to slowly break apart), the player will be swarmed upon by an army of green clones mass-produced to the same likeness as the kidnapped soldier. Fighting through these clones, the player will happen upon a stasis chamber holding the kidnapped soldier in suspended in a spherical tank of unknown fluid. The clones continue to attack the player until at last, the stasis membrane of the chamber is shattered, freeing the soldier and disintegrating the now hostless clones.
Not all the clones died so simply, however, with most of the surviving clones being corrupted into zombies in the process. They, along with the remaining normal clones, attempt to impede the soldiers' escape from the rapidly deteriorating Rugname. Upon opening the ship's bay doors, both forms of clones are pulled into the vacuum of space, where they presumably perish.
Clones typically survive no more than three rounds each, making them extremely frail. To compensate, they often pack heavy weaponry normally used by the player, such as Heavy Machine Gun or Flame Shot. Much like the player, clones also carry knives for close combat and grenades.
Zombie clones don't fire their weapons, preferring to use their vomit attacks periodically. They are substantially stronger than regular clones, requiring six melee strikes to kill whereas regular clones take only one. Zombies take time to turn around, meaning jumping over their heads can buy time to take them out before they can strike.
|Clone Marco: A cloned variant of Marco Rossi. In Metal Slug Attack, a zombie variant also appears after being defeated in its clone form.|
|Clone Tarma: A cloned variant of Tarma Roving. In Metal Slug Attack, they're separated into two units - an actual clone and a zombified version. The clone version uses a shotgun, while the zombified version uses a pistol and blood pukes.|
|Clone Eri: A cloned variant of Eri Kasamoto.|
|Clone Fio: A cloned variant of Fio Germi. In Metal Slug Attack, they're separated into two units - an actual clone and a zombified version.|
|Clone Abby: A cloned variant of Abigail. Appears to be more mechanical than clone based.|
|Clone Betty: A cloned variant of Beatriz. Similarly to her sister model, she is more mechanical than clone based.|
|Clone Trevor: A cloned variant of Trevor Spacey following his brief abduction by the Martians during the second summer event in Metal Slug Attack. They utilize their Two Machine Guns and spiked boots to attack enemies with nimble speed.|
- The clones are a reference to the film Invasion of the Body Snatchers.
- All of the Clones (including Zombie Clones) uses the respective character's death sound when as a Zombie.
- The clones' death animations (excluding zombie clones) are almost identical to animations used when the characters are struck by acid. An additional animation is added upon death of the clones where they break down physically into puddles of liquid.
- Strangely, for the Eri and Fio clones, they re-use the Acid death animation when being hit in the air. which is slightly censored. They will hit the ground but will simply disappear in green liquid, instead of where they land with their rear facing the screen and their shorts melt off, revealing their butt. The sprites exist but are not seen in-game. The on-ground death (where their shirt melts off and reveals their chest) remains unchanged.
- Tarma's clones lack the trademarked sunglasses. Oddly, the zombie Tarma clones still retain the sunglasses.
- In Metal Slug 6, the brainwashed soldier encountered just prior to the final boss has the same sprites as a clone, only with their regular color scheme instead of all green.
- Clone Fio in Metal Slug Attack uses a palette swap of regular Fio instead of her clone sprites.