Summary
Dungeons & Dragonstends to be filled with mindless monsters acting on instinct and terrorizing whatever nearby town they happen to be close to. While others have a base level human intelligence and can be reasoned with, few have Intelligence scores over 20 with access to immense knowledge and power.
These kinds of creatures tend to be singular, named characters in the lore of Faerûn and actively participate in the politics, magic, and major events of their respective planes. Others are rare and reclusive, using their vast intellect to control those they deem lesser from the shadows with their complex plans.
9Fraz-Urb’luu
Mordenkainen Presents: Monsters Of The Multiverse
Known as the Prince of Deception and Demon Lord of Illusions, Fraz-Urb’luu is a demon tied for the highest Intelligence score among all monsters in Fifth Edition. Fraz-Urb’luu is such a terrifyingly powerful caster and deceiver that even his own servants do not know who they truly serve.
While in his lair, Fraz-Urb’luu is nearly unbeatable without the help of antimagic effects and resistance to charm and fear spells due to his accessibility of mind-altering magic. Unlike devils, Fraz-Urb’luu prefers to use illusory magic to deceive, cheat, lie, and steal rather than with words, making him especially difficult to understand.
8Zariel
Baldur’s Gate: Descent Into Avernus
Once an angel turnedarchdevil of Avernus, Zariel is more than just a deadly warrior but a deceiver of the highest rank, especially when crafting unbreakable pacts with mortals. Either through arrogance or confidence in her intelligence, Zariel seeks the strongest and most fearsome heroes in all of Faerûn to craft Lemures for the Blood War.
Where her intelligence really shines, however, is in her battle tactics and ability to inspire loyalty through all kinds of inventive and tortuous methods. Mechanically, Zariel has access to high-level spells and a ridiculously high spell save DC that makes her dangerous in every possible way.
7Solar
Monster Manual
A celestial being ranked high on the divine, cosmological hierarchy, a Solar is a servant of good-aligned deities and acts as a blinding light of justice. Solars have no tolerance for evil and deception, and have a passive ability called Divine Awareness that allows them to permanently detect all lies.
Other than just high-level spellcasting, the ability to communicate telepathically, and 120 feet of true sight, a Solar represents the collective will of the divine and the ability to see everything as it truly is. The only problem is this can make roleplaying a Solar extremely difficult without sounding at least a little corny.
According to lore, only 24 Solar are said to exist at all.
6Sibriex
As disgusting as they are cunning, a Sibriex is a levitating mass of flesh, bile, and blood. Home to the abyss, these demons seek to hoard information, especially ancient lore, while creating new abominations out of those foolish enough to grant it new knowledge.
Although it has access to some low-level spells, the Sibriex’s main ability is Warp Creature, which slowly exhausts the target until they become a fleshy abomination themselves. Although a Sibriex has relatively low hit points compared to other DC 18 creatures, their cunning and constant planning is what makes them both valuable asset and a deadly foe.
5Titivilus
Another devil of the Nine Hells, Titivilus is the advisor to the Lord of Dis and master politician who is always scheming and plotting against stronger devils. Using his limited position of power, Titivilus negotiates demonic pacts and eliminates rivals through deception and guile.
Mechanically, Titivilus is given all of these skills in the form of unique abilities like Corrupting Guidance and Twisting Words, which allow him to control the perception of his enemies. Even just being able to throw his voice up to 60 feet away gives Titivilus all the tools in the Nine Hells to become an apex trickster.
4Nagpa
Cursed by the Raven Queen to forever and only seek ancient knowledge, a Nagpa is a highly intelligent monstrosity that convinces unsuspecting victims to become accomplices in their research of destruction. Since all Nagpas were once powerful wizards, they have access to high-level spells and knowledge of the arcane.
Also being shrewd and cowardly, Nagpas rely on their intelligence and plotting to bring about their plans, waiting for when their opponents are at their weakest before they strike a blow. Nagpas can also work together, filling in the missing pieces of their vast knowledge.
3Star Spawn Seer
Capable of glimpsing the infinite horrors of their Elder Evil masters, a Star Spawn Seer is the spiritual and functional leader of these nightmarish cults. After the fleshy mass has claimed a humanoid victim, it becomes a Seer with access to incredibly powerful gravity-based magic and psychic abilities.
What makes their intelligence unique is that they are entirely alien to the material plane and rely on the knowledge given to them from Elder Evils in their realms of chaos. However, this knowledge runs deep into their distorted psyche and encompasses all kinds of eldritch horrors.
2Elder Oblex
An ooze with the ability to steal the bodies of its victims, Elder Oblex also consumes the memories and intelligence of these humanoids, leading them to target wizards, scholars, and philosophers. With each victim, the Elder Oblex increases their awareness of the outside world, becoming infinitely more dangerous.
This can allow you to determine what kind of knowledge an Elder Oblex would have that varies greatlybetween each oozedepending on what meals they happen to have access to. Regardless of their material knowledge, Oblex are cunning liars and can perfectly simulate any humanoid they consume.
1Elder Brain
A powerful illithid creature that dominates the minds of all who enter its domain,including allied mind flayers, an Elder Brain has a near-infinite well of knowledge, able to concoct plans within plans within plans. An Elder Brain’s role in an illithid colony is to control every element possible at all times.
What would be a taxing, mental load for any being, an Elder Brain only gets stronger the more minds it has under its control. This is represented by its Psychic Link skill, which gives it access to multiple abilities that can weaken its enemies with just a thought.
