Growth & Cline are new characters introduced in Metal Slug Attack.
The two are mercenaries hired by the Rebel Army. Cline is the smaller woman, while Growth is the larger, muscular one. Cline has a rather energetic personality, while Growth is completely silent. Despite their glaring differences, they are good friends and Cline is the only one who understands Growth. They can be easily distinguished on the battlefield with their signature berets.
Cline uses shortswords and her speed to overpower enemies, while Growth's massive strength allows her to carry Bull Chans with her bare hands and toss them at the enemy. Cline is the primary fighter of the duo (as shown in-game), with Growth serving as her support. Growth appears to have some ninja training, as she disappears soon after Cline cuts the Bull Chan and extracts her from the battlefield if it gets too dangerous.
The two are notorious for causing friendly-fire incidents, though it is more likely to be a rumor.
First appearing in the Extra Ops "United Front the 14th", the pair are called in to assist the Rebel Army in an operation against the Ptolemaic Army. Their appearance quickly intimidates the Rebel soldiers due to rumors of them causing friendly-fire incidents. Cline is annoyed that their allies are calling them monsters, while Growth feels that they are right. Cline reassures Growth and the two give it their all so they can return home.
After the battle, the pair seem to have developed a crush on two members of the Ptolemaic Army - Cline likes Damian due to his mysteriousness, while Growth likes Owen due to his alluring tolerance. They then use their remaining coins to buy an avatar icon after a short discussion about the two men.
They're later called in by Navy to participate in a Try Line operation, where Cline expresses concern over having Jane Doe their combat medic. Growth is injured protecting Cline during the operation, and Cline attempts to visit her, only to find herself unable to enter. Navy informs her that it is the intensive care unit, causing Cline to threaten Jane through the door if she attempted anything on Growth. Inside, Jane hears Cline's yelling and simply "replaces" Growth's arm, the latter unable to resist due to her wounds.
- Both characters bear a resemblance to the Delta Red special forces from the Street Fighter series.
- Growth's hairstyle is incredibly similar to Shermie from the King of Fighters, with the only difference besides hair color is that Growth has a short pony-tail while Shermie has two long pony-tails.
- When Cline loses all of her health, she is simply knocked back and stunned before Growth appears and grabs her before disappearing. This makes Cline the fourth Rebel Army character that doesn't die.