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

Regeneration. The ooze regains 10 hit points at the start of its turn. If the pudding takes cold damage, this trait doesn’t function at the start of the pudding’s next turn. The pudding dies only if it starts its turn with 0 hit points and doesn’t regenerate.

Multiattack. The ooze makes three attacks, at least two of which are bite.

Bite. Melee Weapon Attack: +6 to hit, reach 10 ft., 1 target. Hit: 26 (6d6 + 5) piercing damage. 

Slam. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 16 (2d10 + 5) bludgeoning damage. If the target is a creature, it must succeed on a DC 12 Constitution saving throw or have its hit point maximum reduced by an amount equal to the damage taken. The target dies if this attack reduces its hit point maximum to 0. The reduction lasts until removed by the greater restoration spell or other magic.

Extended Grasp. Ranged Weapon Attack: +6 to hit, range 30 ft., one target. Hit: 18 (2d12 + 5) piercing damage. If the target is Medium or smaller, it is grappled (escape DC 15), pulled up to 30 feet toward the ooze, and restrained until the grapple ends. The ooze can grapple three target at a time with its free toothy maws.

Psychic Crush (Recharge 5–6). The ooze targets one creature that it can sense within 60 feet of it. The target must make a DC 16 Intelligence saving throw, taking 10 (3d6) psychic damage on a failed save, or half as much damage on a successful one.