The Cyclobster is a monstrous mutant jellyfish, exclusive to Metal Slug Attack. It first made its debut on the game's event titled 'Try Line 5th', where the boss can also become a playable unit.


A new type of giant mutant weapon discovered by the Ptolemaic Army. It seems likely that it evolved from a mutant weapon discarded by the Rebel Army. With strength beyond any known creature, it destroys everything it sees with its huge and mighty tentacles.

~Metal Slug Attack in-game description.


In Metal Slug Attack's event, This boss is fought at the last stage. It uses its barbed oral tentacles to attack the player's units with its oral tentacles. The player also must be cautious as its attacks are capable of stunning the player's units.

The special attack of the boss lets it fly up out of the map before it subjects an area with flurries of stabs with its large tentacles (duration extended with MSA Skill small + 4). The boss invulnerable and immune to attacks for the entire duration of the special attack, and to add insult to the injury: This attack cannot be baited at all by any means.

Once done with its special attack, it will return to the nearest unit that went past over it while performing its special attack. The player must use his/her units' disables otherwise the boss will wreak havoc.



  • The boss has several unused sprites in its sheet. It includes a glowing eye similar to the Sol Dae Rokker.
  • Its name is derived from the words "Cyclops", a one-eyed Greek mythological giants and a "Lobster", a type of crustacean.
Metal Slug Tetsuyuki | Hairbuster Riberts | Tani Oh | Shoe & Karn | Iron Nokana | Hi-Do

Mini-Bata | Allen O'Neil

Metal Slug 2/X The Keesi II / Iron Nokana MK II (X) | Aeshi Nero | Dragon Nosuke | Big Shiee | Hozmi | Rugname

Mosque Artillery | The Keesi II (X) | Allen O'Neil | Dai-Manji

Metal Slug 3 Huge Hermit | The Ten Commandments of Moses | Jupiter King | Sol Dae Rokker | Rootmars

Twin Ohumein-Conga | Monoeyes | Hairbuster Riberts | Hi-Do | Rugname

Metal Slug 4 Brave Guerrier | Toschka Dalanue | The Iron | Big John | Sea Satan | Amadeus Mother Computer

Mecha Allen O'Neil

Metal Slug 5 Metal Rear | Shooting Ray | Wall Crawler | Sand Marine | Evil Spirit Incarnate

Black Hound | Stone Turtle (unused) | Mammoth Tower | Ptolemaios (unused)

Metal Slug 6 Bull Drill | Iron Sentinel | Brain Robot | Sea Worm | Invader Queen

Invader Controller

Metal Slug 7/XX Worm Mecha | Crablops | Destroyed Crablops | Fall Mecha | The Union | Rebel Gigant | Kraken
Metal Slug: 1st Mission Rebel VTOL | Rebel Train | Macba | Rebel Zeppelin | Electromagnetic Crane | Weapons Port Boss | Hilde Garn

Facility Elevator | Macba | Rebel Truck

Metal Slug: 2nd Mission Big Bertha | Terrain Carrier | Rebel Reactor | Macba | Rebel Submarine | Tani Oh | Gunslinger | Rebel Submarine | Rebel Airplane | Hilde Garn's Slug | Rocket UFO

Rebel Rocket | Hyakutaro

Metal Slug Advance Formor | Emain Macha | Kaladgolg | The Keesi III | Cabracan

Allen Jr.

Metal Slug 3D M-3 Rocket Launch Support Van | Mosque Artillery | Spider-Bot | Underground Cruise Missile | Morden's Battleship | Morden's Castle | Allen O'Neil | Lugus | Lieu
Metal Slug Attack Pharaoh's Arc | Ball Slug | Great Mother | K-O3 Coupled Armored Vehicle | Land Blowfish | Cyclobster | Slug Square | Zoni Doloma
Mobile games Rocket Control Room | Unknown Alien | Hellfire | Spiderbot | Cyclops | Mega Laser Turret | Mars Battle UFO | M-32 Water Carrier Plane | Kourai | Alien Floating Structure