Amaymon Legionary

Amorphous. The demonic ooze can move through a space as narrow as 1 inch wide without squeezing.

Corrode Metal. Any nonmagical weapon made of metal that hits the demonic ooze 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 demonic ooze is destroyed after dealing damage.

False Appearance. While the ooze remains motionless, it is indistinguishable from an oily pool.

Pseudopod. Melee Weapon Attack: +3 to hit, reach 5 ft., one target. Hit: 4 (1d6 + 1) bludgeoning damage plus 7 (2d6) acid damage, and if the target is wearing nonmagical metal armor, 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.

Poisonous Spit. Ranged Weapon Attack: +4 to hit, range 10/50 ft., one target. Hit: 4 (1d4 + 2) bludgeoning damage. Target must make a constitution save or take an additional 4 (1d4+2) poison damage.

Evaporate. When this demonic ooze's HP drops to 0, it evaporates into a cloud of poisonous gas. Anyone within a 50-foot radius must make a constitution save or take 1d4 poison damage. On a critical fail the creature has fallen ill and must continue taking 1d4 necrotic damage each turn until incapacitated or the illness is removed.