Charge. If the snail moves at least 20 feet straight toward a target and then hits it with a slam attack on the same turn, the target takes an extra 4 (1d8) bludgeoning damage. If the target is a creature, it must succeed on a DC 13 Strength saving throw or be knocked prone.

Relentless (Recharges after a Short or Long Rest). If the snail takes 7 damage or less that would reduce it to 0 hit points, it is reduced to 1 hit point instead.

Adamantine Shell. The snail is immune to critical hits.

Amphibious. The snail can breathe in both air and water.

Deepsight. Thriving in deep, warm places, iron snails have little need for sight in the wild, but they are sensitive to movement around them.

Slam. Melee Weapon Attack: +3 to hit, reach 5 ft., one target. Hit: 6 (1d8 + 2) bludgeoning damage.

Steam Burst (recharge 5/6). When the snail is struck with a melee attack, it can force the attacker to make a DC 13 Dexterity check, taking 5 (1d6 + 2) fire damage on a failed save.