The pudding can move through a space as narrow as 1 inch wide without squeezing.
A creature that touches the pudding or hits it with a melee attack while within 5 feet of it takes 4 (1d8) acid damage. Any nonmagical weapon made of metal or wood that hits the pudding 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 or wood that hits the pudding is destroyed after dealing damage.
The pudding can eat through 2-inch-thick, nonmagical wood or metal in 1 round.
The pudding can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.
Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 6 (1d6 + 3) bludgeoning damage plus 18 (4d8) acid damage. In addition, nonmagical armor worn by the target is partly dissolved 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.