Large aberration (mythos), chaotic evil

Armor Class 19 (natural armor)
Hit Points 119 (14d10+42)
Speed 50 ft., climb 20 ft., fly 20 ft. (hover)

20 (+5) 15 (+2) 17 (+3) 16 (+3) 16 (+3) 19 (+4)

Skills Perception +7, Stealth +10
Damage Resistances lightning; bludgeoning that is nonmagical
Damage Immunities cold, poison
Condition Immunities poisoned, blinded
Senses blindsight 90 ft. (blind beyond this radius); passive Perception 17
Languages understands Deep Speech but can�t speak; telepathy 300 ft.
Challenge 9 (5,000 XP)

Special Traits

  • Amorphous. A moon-beast can squeeze through a space that is large enough for a Small creature.
  • Breathless. Moon-beasts do not need to breathe.
  • Innate Spellcasting. The moon-beast�s innate spellcasting ability is Charisma (spell save DC 16). It can innately cast the following spells, requiring no material components:
    • At will: detect thoughts
    • 3/day each: dominate monster, dominate person
    • 1/day each: confusion, major image, mirage arcane, plane shift (self only), seeming
  • Magic Resistance. The moon-beast has advantage on saving throws against spells and other magical effects.


  • Multiattack. The moon-beast makes two attacks: once with its claws and once with its tentacles.
  • Claws. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 19 (4d6 + 5) slashing damage.
  • Tentacles. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 22 (5d6 + 5) bludgeoning damage, and the target must make a DC 16 Wisdom saving throw. On a failed saving throw, the target takes 5 (1d10) psychic damage and its maximum hit point decreases by the same amount. This reduction lasts until the target finishes a long rest. The target dies if this effect reduces its hit point maximum to 0.


Moon-beasts have no voice or eyes, yet they see more than most and can project their thoughts into the very minds of those they wish to communicate with. These monstrosities hail not from any physical moon, but rather from the shared satellite of all slumbering minds in the Dimension of Dream beyond the wall of sleep. Here, the moon-beasts raise stone cities on the oily shores of night-black seas found upon the dark side of the dreaming moon, from which they launch long, dark galleys crewed by not-quite-human slaves that sail through the void of space down to the seas of the Dimension of Dream to seek new slaves and stranger, more sinister wares.

A moon-beast is 9 feet long and weighs 800 pounds.

Slave-Hunters. Moon-beasts are slavers, first and foremost.

They use their magic to curb rebellion or to quickly gain minions, but much prefer using physical and mental regimens of torment and reconditioning to break the spirit of their captives. They often work with the denizens of Leng, a metaphysically nearby dimension of nightmare and madness, although as often as not these planar neighbors serve the moon-beasts merely as slaves.

Mythos Worship. Worshipers of ageless entities from beyond the stars, moon-beasts are often compelled to travel to the Material Plane for strange and frightening causes, not the least of which is gathering suitable sacrifices for their mysterious and demanding lords.

Section 15: Copyright Notice

Mythos Monsters (5E) © 2020, Legendary Games; Authors Michael "solomani" Mifsud, Robert J. Grady, Mark Hart, Jeff Ibach, Alex Riggs, Scott D. Young, Jeff Lee, Matt Kimmel, and Jason Nelson.

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