King Aetherion

gargantuan fiend (demon), chaotic evil

Challenge 25.0 (50,000 XP)

STR
30 (+10)
DEX
18 (+4)
CON
25 (+7)
INT
22 (+6)
WIS
20 (+5)
CHA
28 (+9)

Defense

Armor Class
23 (natural)
Hit Points
480 (30d20+150 +5)
Speed
60 ft., fly 120 ft., swim 60 ft., climb 60 ft., burrow 50 ft., (hover)

Treasure & Loot Common

No significant treasure

Proficiencies & Senses

Saving Throws constitution, wisdom, charisma
Skills
Arcana +14, Nature +12, History +14, Insight +12, Stealth +9, Medicine +5, Religion +14, Survival +12, Athletics +10, Deception +17, Acrobatics +5, Perception +12, Persuasion +17, Performance +9, Intimidation +17, Investigation +14, Sleight of hand +4
Senses
darkvision 120 ft.
blindsight 30 ft.
tremorsense 60 ft.
truesight 60 ft.
Elemental Sense 100 ft. (Can sense elemental energies in a 100 ft radius.)
passive Perception 22

Characteristics

Damage Vulnerabilities
Damage Resistances
fire, cold, lightning, slashing, piercing, bludgeoning from nonmagical weapons
Damage Immunities
poison, psychic
Condition Immunities
charmed, frightened, paralyzed, poisoned
Languages Infernal, Draconic, Common, can understand all languages but can only speak Infernal and Draconic

Traits

Legendary Resistance (3/Day)

If King Aetherion fails a saving throw, he can choose to succeed instead.

Demon's Breath

Every time Aetherion takes damage, he unleashes a wave of demonic energy. Each creature within 30 feet must make a DC 22 Constitution saving throw, taking 66 (12d10) necrotic damage on a failed save, or half as much damage on a successful one.

Elemental Dominion

Aetherion can summon one elemental creature of CR 15 or less as a bonus action, which obeys his commands until slain or dismissed.

Fearsome Presence

Creatures within 60 feet must succeed on a DC 22 Wisdom saving throw or be frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on a success.

King of the Demonic Realm

Aetherion can teleport up to 120 feet to an unoccupied space he can see, which may lead to another demonic realm.

Actions

Multiattack

Aetherion can make three attacks: one with his Bite and two with his Claws.

Bite

Melee Weapon Attack: +17 to hit, reach 10 ft., one target. Hit: 32 (4d10 + 10) piercing damage plus 14 (4d6) necrotic damage.

Claw

Melee Weapon Attack: +17 to hit, reach 10 ft., one target. Hit: 28 (4d8 + 10) slashing damage.

Elemental Fury

Aetherion channels elemental power into a blast of selected energy (fire, ice, or lightning) that is 120 ft. long and 20 ft. wide. Each creature in its path must make a DC 22 Dexterity saving throw, taking 66 (12d10) damage on a failed save, or half as much damage on a success.

Combat Behavior

Tactics


• Use fear-inducing abilities to weaken foes before engaging in direct combat.
• Regularly summon elementals to distract and swarm enemies while he attacks from a distance.
• Utilize teleportation to evade difficult encounters and control battlefield positioning.

Combat Style

Aetherion employs a strategic combat style, leveraging his ability to control the elements around him while utilizing psychological manipulation to instill fear.

Morale

Aetherion fights until the end as long as he is able to inflict maximum damage on his foes. He strategizes his retreat when significantly outnumbered or if severely injured, opting to regroup and re-strategize with his minions.

Monster Description

King Aetherion is an imposing figure that represents the fusion of various elemental powers with demonic authority. Towering at a height of over 25 feet, he is draped in flames that flicker in hues of crimson and gold. His body is a mix of scaly hides, reminiscent of ancient dragons, and covered in the markings of elemental energy. His eyes burn like molten lava, revealing an intelligence that is both cunning and malicious. He commands an army of lesser demons and elementals that fear his wrath, swearing allegiance to him for the power he grants them. Aetherion's roars can shake the very foundations of reality, resonating with echoes of both primal ferocity and celestial chaos. His spirit is tied to the elemental planes, allowing him to manipulate fire, ice, and lightning effortlessly.

Aetherion resides in a massive citadel made from black iron and surrounded by a constantly swirling haze of elemental chaos. The ground beneath is scorched and cracked, creating rivers of molten lava that form a barrier to unwanted visitors. Only through the toughest trials can one truly gain audience with him, and most who enter his domain prey at the altar of their own terror. King Aetherion is not your typical demon lord; his ambitions extend beyond mere conquest. He seeks to unravel the fabric of reality, hoping to merge the elemental planes with the material realm. In his eyes, chaos and entropy are the true nature of existence, one that he is destined to reign over. He revels in the devastation he causes, leaving behind the ashes of civilization in a perverse display of his power.

The King of Demons, Dragons, Wolves, and Elementals embodies the very essence of fear and dominance. His ambition has not gone unnoticed, and many powerful entities seek to contain or destroy him to maintain the balance of the planes. But such attempts have been thwarted by his incredible might and his mastery of all elemental forms. His pursuit of complete control over all realms is a constant source of disturbance, and many heroes rise and fall in their attempts to thwart him, only to be consumed by his insatiable hunger for power and chaos.

Monster behavior

King Aetherion employs a brutal combat style that combines elemental abilities with mind games. He revels in inspiring fear in his enemies, often using intimidation tactics to break their will before engaging in physical combat. In battle, he utilizes his ability to teleport to keep his foes off-balance, striking from unexpected angles and retreating before they can retaliate. His attacks are coordinated, often summoning elementals to distract and divide his opponents. He is known to apply psychological warfare, taunting his enemies with visions of their doom and exploiting their fears. When overwhelmed, Aetherion has no qualms about using hit-and-run tactics or retreating to prevent his own defeat.

Each of Aetherion’s attacks is calculated to maximize damage and instill terror. He understands the importance of controlling the battlefield, manipulating flames and elemental forces to create hazards that slow or damage adversaries. During combat, he often commands his elemental minions to harass opponents, allowing him to strike from a distance with his powerful energy attacks. Those who survive a confrontation with Aetherion often find themselves reporting stories of millennia, pooling together to confront him as he becomes more of a legend than a monster. Many warriors have since immortalized his name and taken it as a challenge they must face.

Ecology

In terms of ecology, Aetherion is a top-tier predator in his dominion. By maintaining dominance over lesser demons and elementals, he shapes the landscape of chaos around him. His presence warps the natural order, creating an ecosystem where only the strongest survive. Elementals that serve under him are often tasked with maintaining the elemental rifts that connect various planes, acting as liaisons between realms. In his absence, the levels of chaos would fluctuate, leading to instability in the elemental planes. Lesser demons act as both shock troops and servants, scavenging the material realm for resources and souls to bring back to their lord.

King Aetherion's influence has attracted other predators, both elemental and demonic, turning his territory into an arena of violence and survival. Creatures spawned from lesser demons and chaotic energies persist in his wake, often adapting to the chaotic environment. The imbalance created by his reign leads to the emergence of new elemental beings, formed from the chaos of both the elemental and the infernal realms. As a creature of power, he is a catalyst for change and transformation, ensuring that the elemental creatures that surround him serve his ambitions while maintaining the cycle of destruction and rebirth in the landscape.

History

Born from the chaotic energies of the Abyss, King Aetherion ascended to power through sheer will and destruction. As lesser demon factions warred for dominance, Aetherion emerged as a significant player within the chaos, gathering numerous legions of both demons and elementals under his banner. Over centuries, he honed his abilities, commanding the elemental forces that echoed through the multiverse, cementing his position as the king of demons and elementals. There have been many attempts to dethrone Aetherion; however, he has thwarted each challenge with brutality, ensuring that no opposing force stands a chance against him. This record of triumphs has contributed to his infamous reputation and unrivaled command over the demonic realm.

Legends speak of a time when he sought to merge the elemental planes into a singular chaotic existence, thus expanding his influence beyond the material world. Heroes from various realms have embarked on quests to put an end to his machinations, but none have succeeded, further enhancing his mythos as an invincible tyrant.

Today, King Aetherion stands as a symbol of entropy and chaos, a tyrant whose aspirations are a constant source of concern for the inhabitants of multiple dimensions. Elders warn that the day he successfully merges the realms will usher in an era of unstoppable chaos. Thus, the war against the overwhelming power of King Aetherion wages on, an indelible part of the storylines across valleys, kingdoms, and the very fabric of existence.

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