Armor Class 17 (natural armor)
Hit Points 19 (3d8 + 6)
Speed 10 ft.
Damage Immunities poison
Condition Immunities charmed, exhaustion, frightened, petrified, poisoned
Senses passive Perception 9
Languages the languages it knew in life
Challenge 1
Cunning Opportunist. The stone cursed has advantage on the attack rolls of opportunity attacks.
False Appearance. If the stone cursed is motionless at the start of combat, it has advantage on its initiative roll. Moreover, if a creature hasn't observed the stone cursed move or act, that creature must succeed on a DC 18 Intelligence (Investigation) check to discern that the stone cursed isn't a statue.
Unusual Nature. The stone cursed doesn't require air, food, drink, or sleep.
Petrifying Claws. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 12 (2d8 + 3) slashing damage. If the target is a creature, it must succeed on a DC 12 Constitution saving throw, or it begins to turn to stone and is restrained until the end of its next turn, when it must repeat the saving throw. The effect ends if the second save is successful; otherwise the target is petrified for 24 hours.
Mordenkainen Presents: Monsters of the Multiverse, p. 233