Ooze Master

Huge undead, Lawful Evil

Armor Class

9 (natural armor)

Hit Points

138 (12d12+60)

Speed

walk 30 ft., climb 30 ft.

Saves

Int +7, Wis +4

Skills

Arcana +7, Insight +4

Damage Resistances

lightning, necrotic; bludgeoning, piercing, slashing from nonmagical attacks

Damage Immunities

acid, cold, poison

Condition Immunities

blinded, charmed, deafened, exhaustion, frightened, paralyzed, poisoned, prone

Senses

blindsight 120 ft.

Languages

Common, Primordial, Thayan

Challenge

10

Corrosive Form

A creature that touches the Ooze Master or hits it with a melee attack while within 5 feet of it takes 9 (2d8) acid damage. Any nonmagical weapon that hits the Ooze Master 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 that hits the Ooze Master is destroyed after dealing damage. The Ooze Master can eat through 2-inch-thick, nonmagical wood or metal in 1 round.

Instinctive Attack

When the Ooze Master casts a spell with a casting time of 1 action, it can make one pseudopod attack as a bonus action.

Spider Climb

The Ooze Master can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.

Spellcasting

The Ooze Master is a 9th-level spellcaster. Its spellcasting ability is Intelligence (spell save DC 15, +7 to hit with spell attacks). It has the following wizard spells prepared: • Cantrips (at will): acid splash, friends, mage hand, poison spray • 1st level (4 slots): charm person, detect magic, magic missile, ray of sickness • 2nd level (3 slots): detect thoughts, Melf's acid arrow, suggestion • 3rd level (3 slots): fear, slow, stinking cloud • 4th level (3 slots): confusion, Evard's black tentacles • 5th level (1 slots): cloudkill

Actions

Pseudopod

Melee Weapon Attack: +7 to hit, reach 10 ft., one target. Hit: 13 (3d6 + 3) bludgeoning damage plus 10 (3d6) acid damage.