Astral Dreadnoughts glide silently through the mists of the Astral Plane in search of prey. A dreadnought consumes its quarry alive, attempting to fill the emptiness of its existence with the souls of others.

The mere appearance of an astral dreadnought strikes fear into the hearts of its prey. While foes suffer the effect of its gaze, the monster snaps up weak and undefended creatures in its pincer claws, attempting to stuff them into its yawning maw.

Extradimensional Digestion. Any creature the astral dreadnought swallows becomes trapped in a demiplane, where the dreadnought devours their sanity. Only the death of the astral dreadnought can free those it has trapped in this extradimensional space.

Gaze of the Chained God. Astral dreadnoughts were once angels of the Chained God, but their master’s madness corrupted them. Cultists and scholars alike have speculated that if one were to harvest the eyes of enough astral dreadnoughts, he or she might use the combined power to free the Chained God.

Astral Dreadnought

Gargantuan monstrosity, chaotic evil

Armor Class 19 (natural armor)

19 (natural armor) Hit Points 307 (15d20 + 150)

307 (15d20 + 150) Speed 0ft., fly 180 ft. (hover)

STR DEX CON INT WIS CHA 30 (+10) 7 (-2) 30 (+10) 5 (-3) 14 (+2) 18 (+4)

Saving Throws Dex +4, Int +3, Wis +8

Dex +4, Int +3, Wis +8 Skills Stealth +4, Perception +8

Stealth +4, Perception +8 Damage Resistances bludgeoning, piercing, and slashing from nonmagical attacks

bludgeoning, piercing, and slashing from nonmagical attacks Condition Immunities frightened, prone

frightened, prone Senses darkvision 120 ft., passive Perception 18

darkvision 120 ft., passive Perception 18 Languages —

— Challenge 17 (50,000 XP)

Antimagic Cone. The dreadnought's central eye creates an area of antimagic, as in the antimagic field spell, in a 150-foot cone. At the start of each of its turns, the dreadnought decides which way the cone faces and whether the cone is active.

All magical effects within the cone are suppressed, except for those that brought the subjects to the Astral Plane in the first place (the astral projection spell, for example). Those effects are locked in place while the subjects are in the cone and cannot be dismissed, trapping the subjects on the Astral Plane while under its effect.

Magic Resistance. The dreadnought has advantage on saving throws against spells and other magical effects.

Magic Weapons. The dreadnought's weapon attacks are magical.

Actions

Multiattack. The dreadnought can use its Frightful Presence. It then makes three attacks: one with its bite and two with its pincers.

Pincer. Melee Weapon Attack: +16 to hit, reach 5 ft., one target. Hit: 17 (2d6 + 10) slashing damage, and the target is grappled (escape DC 20). Until this grapple ends, the target is restrained. On a critical hit against a target in an astral body (as with the astral projection spell), the dreadnought cuts the silvery cord that tethers the target to its material body.

Bite. Melee Weapon Attack: +16 to hit, reach 10 ft., one target. Hit: 21 (2dl0 + 10) piercing damage. If the target is a Huge or smaller creature, it must succeed on a DC 20 Dexterity saving throw or be swallowed by the dreadnought.

While swallowed, the target enters a dimly lit 40-foot spherical demiplane. The swallowed creature arrives in a space of the dreadnought's choosing. A Large hovering eyeball occupies the center of the demiplane.

Creatures in the demiplane can attack the eye. It shares the dreadnought's statistics, except that it is resistant to all damage except force and psychic damage, and immune to teleportation and forced movement. Any damage or effects the eye takes are also applied to the astral dreadnought.

At the start of each of the dreadnought's turns, all swallowed creatures must make a DC 20 Wisdom saving throw. On a failed save, the creature takes 27 (6d8) psychic damage and is confused (as the spell confusion) until the start of the dreadnought's next turn. On a successful save, the target takes half damage and is not confused. A creature reduced to 0 hit points by this damage and survives is permanently insane, with effects determined by the DM, until cured by remove curse or similar magic.

When an astral dreadnought dies, the swallowed creatures are expelled into the space the dreadnought formerly occupied.

Frightful Presence. Each creature of the dreadnought's choice that is within 120 feet of the dreadnought and aware of it must succeed on a DC 20 Wisdom saving throw or become frightened for l minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to the dreadnought's Frightful Presence for the next 24 hours.