The Big Snail is an enemy in Metal Slug 3.


These malevolent mutated molluscs live in humid and dirty places, and can only be found in the lowest paths of Mission 4. They can spit acid and hide in their shells when attacked, which will deflect bullets. When killed while on a ceiling, the shell is left behind and becomes an explosive hazard. Sometime it will hide in it shell and self-destruct.

Using Drill Slug is the best way to dispatch them, as the drill will destroy the snail and their shell as well, occasionally dropping bonus items.

In Metal Slug Defense, the Big Snail can be bought from the unit shop for 40 Medals, and costs about 120 AP per unit. Its normal attack is its acid spit, and special attack is hiding in its shell, which will make it immune to all forms of attacks for a few seconds but renders it immobile, unlike the Shielded Soldier and Shielded Guerilla units.


  • When a Big Snail, Maggots or a Giant Caterpillar's acid hits a male character, his flesh dissolves into nothing but bones. If a female character is hit by the acid, her clothes will dissolve first, exposing her naked breasts or buttocks, depending on whether she was hit while standing or jumping. Her body then melts away into green slime as she dies.

Sample of dissolved Eri hit by snail

Human Rebel Infantry | Arabian Infantry | Japanese Infantry | Pirates | Scientists | Ptolemaic Infantry | Natives | Hunters | Future Rebels
Undead Mummies (Mummy Generator) | Dog Mummy | Mutated Soldiers | Zombies | Tar Man | Clones
Mutant Bat | Chowmein-Conga | Ohumein-Conga | Enormous Moray | Jellyfish | Flying Killer | Man Eater | Huge Locust | Sasquatch | Maggot | Big Snail | Giant Caterpillar | Squid | Huge Ivy
Alien Monoeye | Ring Laser Mecha | Hopper Mecha | Mars Mecha | Mars People | Big Eye | UFO | Mini-UFO | Invader Squad | Winged Invader | Flying Parasite | Hunter Walker | Hunter Lord | Scavenger | Crab-Tank | Vanguard | Smasher | Invader UFO | Indestructible UFO | Flying Core