Amorphous. The slime can move through a space as narrow as 5 inches wide without squeezing.

Corrode Metal. Any nonmagical weapon made of metal that hits the slime corrodes. After dealing damage, the weapon takes a permanent and cumulative −1 penalty to damage rolls. If its penalty drops to −5, the weapon is destroyed. Nonmagical ammunition made of metal that hits the slime is destroyed after dealing damage.

The ooze can eat through 4-inch-thick, nonmagical metal in 1 round.

Acidic Presence. The nonmagical land that the slime lands on turns into bubbly acidic sludge after 1 round of the slime being there. The land turns back to normal 2 minutes after the slime moves off of it. Any target that attempts to move the sludge treats it as difficult terrain and takes 2 (1d4) acid damage for every 5 ft they move through.

Any creature that touches or makes a melee attack against the slime while within 5 ft of it takes 3 (1d6) acid damage.

Multiattack. The slime makes two pseudopod attacks.

Pseudopod. Melee Weapon Attack: +6 to hit, reach 10 ft., one target. Hit: 4 (1d4 + 2) bludgeoning damage plus 10 (3d6) acid damage, and if the target is wearing nonmagical metal armor, it must succeed on a DC 14 Constitution saving throw or its armor is partly corroded and takes a permanent and cumulative −1 penalty to the AC it offers. The armor is destroyed if the penalty reduces its AC to 10. If a creature takes this acid damage and is vulnerable to acid damage, they take triple damage instead of double damage.