Large Aberration (Beholder), Lawful Evil
Armor Class 20 Natural Armor
Hit Points 400 (32d12 + 192)
Speed 40 ft., Fly 40 ft.
STR
14 (+2)
DEX
16 (+3)
CON
24 (+7)
INT
22 (+6)
WIS
18 (+4)
CHA
21 (+5)
Saving Throws INT +13, WIS +11, CHA +12
Skills Insight +12, Perception +18
Damage Resistances Cold, Fire, Lightning
Damage Immunities Poison, Psychic
Condition Immunities Charmed, Frightened, Prone
Senses Truesight 120 feet, Passive Perception 28
Languages Deep Speech, Telepathy 120 feet, Undercommon Deep speech, Undercommon , Telepathy 120ft
Challenge 23 (50,000 XP)
Proficiency Bonus +7
Traits

Special Traits

Antimagic Cone
The ancient beholder guardian’s central eye emits a 300-foot cone of antimagic, as per the antimagic field spell. At the start of each of its turns, the guardian decides which way the cone faces and whether the cone is active. The area works against the guardian's own eye rays.

Actions

Actions

Multiattack
The ancient beholder guardian makes two bite attacks and uses its Eye Rays. Bite
Melee Weapon Attack: +11 to hit, reach 10 ft., one target. Hit: 27 (6d6 + 9) piercing damage.

Eye Rays
The guardian uses three of the following magical eye rays at random (reroll duplicates), choosing one to three targets within 240 feet of it:

 

1. Charm Ray

The targeted creature must succeed on a DC 20 Wisdom saving throw or be charmed by the guardian for 1 hour, until the guardian harms it, or until it commands the creature to do something it wouldn’t normally do.

2. Paralyzing Ray

The targeted creature must succeed on a DC 22 Constitution saving throw or be paralyzed for 1 minute. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.


3. Fear Ray

The targeted creature must succeed on a DC 20 Wisdom saving throw or be frightened for 1 minute. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.


4. Slowing Ray

The targeted creature must succeed on a DC 22 Dexterity saving throw or be slowed for 1 minute. While slowed, the target’s speed is halved, it cannot use reactions, and it can only make one attack or use one action on its turn. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.


5. Disintegration Ray

The targeted creature must succeed on a DC 24 Dexterity saving throw or take 56 (8d6) force damage. If this damage reduces the target to 0 hit points, its body disintegrates into fine dust, leaving only magical items behind.
 
6. Petrification Ray
The targeted creature must succeed on a DC 22 Dexterity saving throw. On a failed save, the target begins to turn to stone and is restrained. The restrained target must repeat the saving throw at the end of its next turn. On a success, the effect ends. On a failure, the target is petrified until freed by the greater restoration spell or similar magic.

7. Death Ray

The targeted creature must succeed on a DC 24 Constitution saving throw or take 56 (8d6) necrotic damage. If the target dies from this damage, its soul is trapped within the guardian, and it cannot be resurrected by any means short of a wish spell.

8. Gravitic Ray

The targeted creature must succeed on a DC 22 Strength saving throw or be crushed under extreme gravity, taking 54(12d6) bludgeoning damage and being restrained until the end of its next turn. The creature can break free with a DC 22 Strength check on its turn.

9. Mindwrack Ray

The targeted creature must succeed on a DC 22 Intelligence saving throw or take 55(10d6) psychic damage and suffer from short-term madness for 1 minute. The target can repeat the saving throw at the end of each of its turns, ending the madness early on a success.

10. Banishing Ray

The targeted creature must succeed on a DC 24 Charisma saving throw or be banished to a random demiplane for 1 minute. The creature reappears in the space it left or the nearest unoccupied space if that space is occupied.
Bonus Actions

Tactical Insight
The guardian can use a bonus action to grant advantage on attack rolls or saving throws to one ally within 60 feet of it (including itself) until the end of its next turn.

 

Reactions

Deflecting Glare
When a creature within 60 feet of the guardian that it can see hits the guardian with an attack or casts a spell targeting it, the guardian can use its reaction to impose disadvantage on the attack roll or saving throw of the spell.

Legendary Actions

The ancient beholder guardian 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 guardian regains spent legendary actions at the start of its turn.

Eye Ray
The guardian uses one random eye ray.
Antimagic Pulse (Costs 2 Actions)
The guardian emits a pulse of antimagic energy in a 60-foot radius. Each creature in that area must succeed on a DC 22 Constitution saving throw or be unable to cast spells or use magical effects until the end of their next turn.
Maddening Glare (Costs 3 Actions)
The guardian fixes its gaze on one creature it can see within 60 feet of it. The target must make a DC 24 Wisdom saving throw or be driven insane. On a failed save, the target is affected by dominate monster (no concentration required) for 1 minute.

 

Description

Ancient and Watchful
The Ancient Beholder Guardian is a timeless entity that has guarded ancient secrets and treasures for eons. Its gaze is both intimidating and insightful, with a presence that commands respect and fear. The guardian’s central eye pulses with an otherworldly power, capable of suppressing magic and altering reality around it. It is highly intelligent and strategic, using its knowledge and abilities to maintain its dominion over its lair and its treasures. The guardian’s demeanor is cold and calculating, showing little empathy or mercy to those who intrude upon its domain.

Lair and Lair Actions

The lair of the Ancient Beholder Guardian is a vast and eerie cavern, dimly lit by an otherworldly glow emanating from the guardian’s central eye. The walls are covered in strange, shifting patterns that seem to move and writhe, reflecting the guardian's magical influence. The air is thick with a palpable sense of menace, and an unsettling silence is occasionally broken by the faint echo of distant whispers. The lair's floor is uneven and scattered with ancient ruins, relics, and arcane symbols that hint at the guardian’s long history. Several large, crystalline formations jut out from the ground, casting eerie reflections and adding to the disorienting effect of the cavern. In the center of the lair is a raised platform or altar where the guardian typically resides, surrounded by a circle of runes that pulsate with a faint, malevolent light. The platform serves as both a throne and a focal point for its magical powers. Around the lair, subtle traps and magical wards are hidden, designed to deter or ensnare any who dare to trespass. The lair’s atmosphere is thick with an aura of ancient power and the tangible threat of imminent danger, making it a truly formidable domain for any adventurers who challenge its master.

Lair Actions

On initiative count 20 (losing initiative ties), the ancient beholder guardian can take one of the following lair actions:

Gravity Well

The ground in a 60-foot radius centered on a point the guardian can see within 120 feet becomes a gravity well for 1 minute. Each creature in that area must succeed on a DC 22 Strength saving throw or be pulled 30 feet toward the center of the area and be restrained until the end of their next turn.

Abyssal Portal


A swirling portal to a random demiplane opens at a point the guardian can see within 120 feet. Each creature within 30 feet of the portal must succeed on a DC 22 Dexterity saving throw or be pulled into the portal, reappearing in a random location within 60 feet of the portal's original location.

Nightmarish Visions


The guardian conjures nightmarish visions that fill a 60-foot radius centered on a point it can see within 120 feet. Each creature in that area must succeed on a DC 22 Wisdom saving throw or take 44 (8d6) psychic damage and be frightened until the end of their next turn.

Regional Effects

The presence of the Ancient Beholder Guardian in its lair creates the following magical effects within a 1-mile radius:

Distorted Reality
The area within the lair's influence becomes warped and disorienting. The terrain might subtly shift, making navigation difficult. Creatures within this area must succeed on a DC 15 Wisdom saving throw or have disadvantage on Wisdom (Perception) and Intelligence (Investigation) checks.

Antimagic Aura
An aura of antimagic subtly permeates the region, reducing the effectiveness of magic. Spells cast within 1 mile of the lair have their range halved, and magical effects that require concentration are more likely to be disrupted. Concentration checks made within this area have disadvantage.

Ominous Presence
The guardian’s influence instills a pervasive sense of dread. Creatures within the lair’s influence must succeed on a DC 15 Wisdom saving throw at the start of each day or be frightened until the end of their next turn. This effect can be resisted once per day.

 

If the Ancient Beholder Guardian dies, these effects fade over the course of 12d20 days.

 

Previous Versions

Name Date Modified Views Adds Version Actions
7/20/2025 10:57:28 AM
19
6
1
Coming Soon

Monster Tags: Beholderabberation

Habitat: SwampUnderdark

StLUCIFER

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