This is a list of characters and units who debuted in Metal Slug Attack categorized by their army affiliation and association with specific groups. This does not include edits of previous units (such as the Hozmi/Hodumi+ and Jupiter King/Sky Jupiter King). Names in parenthesis represent new and named weapons related to the character.
Regular Army
Assorted Members:
- Anna Wiese
- Midori Schumann (Tetsujin-Kun)
- Mello
- Rita Lewinsky
- Amber (Slug Attacker)
- Nikita
- Reika Bradford
- Louise
- Gisee
- Ashley
- Rocky
- Growl (Tiger Slug)
- Jephet (Coil Tank)
- Victoria (Mecha Falcon "Wade")
- Kanae (Patrol Slug)
- Claudia
- Karen (Slug Sniper)
- Elizabeth Mariani
- Undo
Artificial Intelligence:
Metal Device Project:
- Perche
- Avvio
- Ami
- Molly (Slug Defender)
- Menzel/M.D.P.S-Mz 3
- Ulala
- Maggie (Slug Rising)
- Quaith (Tail Slug)
- Howell
Vehicles and Artillery:
- Ball Slug
- Slug Square
- Giant Copter
- Doll
- Toy Union Cannon
- Digger Base
- Mega Drill Slug
- Super Cannon
- Pile Impact
- 7000 Class Locomotive
- Slug Striker
- Copter Arms
- "3D Printer Tank"
Rebel Army
Assorted Members:
- Rapid (8082 Train)
- Julia
- Chloe (Naglfar) (RJ Bischof)
- Izabella
- Edda
- Growth & Cline
- Naomi (Denturion)
- Alesha (Electriblade)
- Jane Doe
ACE:
"Frozen Brigade":
Blaze Brigade:
Allen Platoon:
Science Department:
- Vita
- Navy
- Nova
- Emma (Recycle Box)
- Millefie (Iwa Oh)
- Sylfie (Fight Cab)
- Fluffy (Fluffymeranian)
- Eight Eight
- Eight Eight's Caretaker
Arabian Infantry:
Vehicles:
Ptolemaic Army
Main Army/Rebellion:
Guerrilla/Army:
- Dragunov
- Caroline (D-Gu)
- Veronica
- Sisilia (La Torne)
- Towa
- Simon
- Owen
- Lucy (Lucy's Frog Mecha)
- Phoebe (D-001 Tanbal)
- Josette
- Little Lady Black
- Svetla (GIP-03 Bergenia)
- Humphrey
- Lithos (Hammer DX5005)
- Yutong (Vermilion Tank)
- Tatyana
- Cica
Ninjas/Mystic Martial Artists
Cultists:
Secret Sect:
- Anastasia IV (Ulyana's Staff)
- Beecham (Snordon)
- Melvina (Glidron)
- Zahara
- Anastasia I
- Zahara
- Believers
Vehicles:
Space Army
Martians and Affiliates
- Professor "Aionion" (Mars Gigantalos)
- Marty
- Percier
- Clone Abby
- Clone Betty
- Ariadna
- Gemini Twins
- Halle
- Bonny
- Clario
- Harriot (Mars Sweeper)
- Code Marionette:Un
- Pauline
- Leone
- Claris
- Unsigned
- Draco
- Raubtier
- Li Lin
- Mars People Rangers
- Psionic Brain
Invaders
Humanoids/Humans/Others:
- Odette
- Annette
- Lydia
- Nowan
- Rillacle
- Franke
- Teleko
- Odile
- Bersek
- Purple King
- Barbeln
- Biene Goldenes
- Swordeist
- Drache Goldenes
- Eis Monstrum
- Ai Agate
- Lieben
Species:
Metzelei/Four Heavenly Kings:
Independent Army
Amadeus Syndicate
Artificial Intelligence/Viruses:
Technology:
Employees:
Pirates:
Mummies
Royalty:
Warrior Priestesses/Servants:
Armies:
Red Goblin Society and Affiliates
- Scotia Amundsen
- Red Goblin (Machyna)
- Vatn
- Jin
- Licht
- Elena (Bushin Tenzan)
- Ichima
- Yuki Tsuki Hana (Kagura, Keisetsu, Ouka, and Tsukikage)
- Maki
Vampires
Underworld Villagers
"World Military Corp."
- Kelly
- Maya
- Mirror Mantis (Super Vibration Cutter)
Mirage Circus
- Cocatrix
- Bunny the Performer
Others
Vehicles
Creatures