Ruby Ooze

Ambusher. The ooze has advantage on attack rolls against any creature it has surprised.

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

Corrosive Form. A creature that touches the ooze or hits it with a melee attack while within 5 feet of it takes 7 (2d6) acid damage. Any nonmagical weapon made of metal or wood that hits the ooze is coated in a corrosive red slime. 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 ooze is destroyed after dealing damage. The ooze can eat through 2-inch-thick, nonmagical wood or metal in 1 round.

False Appearance. While the ooze remains motionless, it is indistinguishable from a pile of rubies.

Spider Climb. The ooze can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.

Multiattack. The ruby ooze makes two pseudopod attacks.

Pseudopod. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 9 (2d6 + 2) bludgeoning damage plus 14 (4d6) acid damage.

Acid Spray (Recharge 5-6). The ooze sprays its bright red protoplasm in a 20-foot line that is 5 feet wide. Each creature in that line must make a DC 15 Dexterity saving throw. On a failure, the creature takes 21 (6d6) acid damage and is restrained as its flesh begins to turn into a translucent ruby-like stone. On a success, the creature takes half the damage and isn't restrained. The restrained creature must make a DC 15 Constitution saving throw at the end of its next turn, taking 21 (6d6) acid damage and becoming petrified on a failure or ending the effect on a success.