For information about this unit in the main series, see Stone Turtle.
|"An ultra-gigantic secret weapon unearthed by the Ptolemaic Army. Due to its gigantic size, the war ended before the excavations."|
The Stone Turtle was originally supposed to be added in Metal Slug 5, but was later then scrapped, however it later appeared in Metal Slug Defense as a purchasable unit, then later at Metal Slug Attack as a Super-Rare Unit.
Its parts can be purchased at the Team Battle shop for 500 Battle Medals (5 parts are obtained each time).
One part can be freely obtained each day via Treasure Hunt. The first chest is free, with all subsequent chests requiring 20,000 MSP. This will require the player to have a VIP level of 5 or higher though.
The Stone Turtle has massive health, but also comes with a very high AP cost (2000 just to send it out). While subsequent frames will cheapen the cost of the Stone Turtle, it is still a very expensive unit. The Stone Turtle's speed can be increased with 1, and its special attacks get stun potential with 2 unlocked.
It basically serves as a damage sponge (as 3 gives it a whopping 20% health boost and 1% extra for each level). In addition to the massive health, having 4 unlocked allows the Stone Turtle to boost the health of its fellow Ptolemaic Army units, essentially mimicking Donald Morden's 2. This helps increase the durability of units like Yoshino and Dragunov.
While Ptolemaios is also capable of buffing the health of Ptolemaic Army units, he is currently unavailable.
Squish - It will stomp its enemies using it's gigantic foot, dealing massive damage in a medium area.
Missile Salvo - 2 missile turrets appear from the side of the Stone Turtle, and shoot out eight rockets (in four sets of two missiles). It also has stun capability (Requires Skill 2 )