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Spelljammer: Adventures in Space

Cosmic Horror CR: 18

Gargantuan aberration, neutral evil
Armor Class: 15
Hit Points: 280
Speed: 50 ft , fly: 100 ft

STR

27 +8

DEX

10 +0

CON

25 +7

INT

24 +7

WIS

15 +2

CHA

24 +7

Saving Throws: INT +13, WIS +8, CHA +13
Damage Immunities: Acid, Poison
Condition Immunities: Charmed, Frightened, Poisoned
Senses: Darkvision 240ft., Passive Perception 12
Languages: Deep Speech, Telepathy 240ft.
Challenge Rating: 18 ( 20000 XP)
Proficiency Bonus: +6

Legendary Resistance (3/Day). If the horror fails a saving throw, it can choose to succeed instead.   Unusual Nature. The horror doesn’t require air.

Actions

Multiattack. The horror makes one Bite attack and two Tentacle attacks.   Bite. Melee Weapon Attack: +14 to hit, reach 10 ft., one target. Hit: 22 (4d6 + 8) piercing damage.   Tentacle. Melee Weapon Attack: +14 to hit, reach 30 ft., one target. Hit: 18 (3d6 + 8) force damage, and if the target is a creature, it is grappled (escape DC 18). Until this grapple ends, the horror can’t use this tentacle against other targets. The horror has 1d8 + 1 tentacles, each of which can grapple one target.   Psychic Whispers (Recharge 5–6). The horror emits dreadful whispers in a 60-foot-radius sphere centered on itself. Each creature in the sphere that isn’t an Aberration must make a DC 21 Wisdom saving throw, taking 33 (6d10) psychic damage on a failed save, or half as much damage on a successful one.

Legendary Actions

The horror can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature’s turn. The horror regains spent legendary actions at the start of its turn.   Crushing Tentacle. The horror crushes one creature it is grappling. The grappled creature must make a DC 22 Constitution saving throw, taking 18 (3d6 + 8) force damage on a failed save, or half as much damage on a successful one.   Poison Jet (Costs 2 Actions). Foul gas squirts from the horror in a 30-foot line that is 5 feet wide. Each creature in the line must succeed on a DC 21 Constitution saving throw or take 14 (4d6) poison damage.   Teleport (Costs 2 Actions). The horror teleports, along with any creatures it is grappling, to an unoccupied space it can see within 120 feet of itself.

Cosmic horrors are colossal, malevolent entities that occasionally slip the bonds of the Far Realm and find themselves adrift on the Astral Plane. Drawn to the light of distant stars, these creatures invade Wildspace systems and lay waste to worlds. After feeding on the minds and bodies of a world’s inhabitants until it is sated, a cosmic horror usually returns to the void, where it falls into a deep sleep, drifting aimlessly until hunger or some other stimulus awakens it.
Cosmic horrors are among the most powerful creatures spawned by the Far Realm. No two of them have the same appearance, but they have certain qualities in common. Each one is roughly 100 feet long or tall, and its physical form is a seemingly impossible conglomeration of eyes, mouths, wings, tentacles, and less recognizable organs and appendages.

Suggested Environments

Astral Plane


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