At last, the Regular Army's secret weapon make its debut! This tank is the largest of all the Regular Army's arsenal, with multiple Regular Army soldiers on board. It protects the base with a variety of bombardments and its impregnable defense.
In Metal Slug Attack's event, this boss is fought at the last stage. The boss will attack the player's units with its Gatling gun. The Regular soldiers on-top of it fires homing bazookas in unison.
The special attack of the boss will also fire 2 cannon blast from its rear and one large cannon shell from its front cannon. The player must be extremely cautious by keeping the boss away from range. As a the special has a very long distance and can pierce.
Slug Square: The original.
Slug Square MK II: A blue variant of the Slug Square which sacrifices some offense and defense. The soldiers on top of the Slug Square are armed with mortars instead.
Golden Slug Square: A golden variant of the Slug Square which was modified and equipped with a missile launch mechanism and a powerful defense device designed specifically to support the front line from the distance.