Cerebrilith Large fiend (demon), chaotic evil Armor Class 15 (natural armor) Hit Points 149 (13d10 + 78) Speed 30 ft. Str 21, Dex 13, Con 23, Int 15, Wis 18, Cha 21 Saving Throws Int +6, Wis +8 Damage Immunities lightning, poison Damage Resistances acid, cold, fire, psychic; bludgeoning, piercing, and slashing from nonmagical attacks Senses darkvision 60 ft. passive Perception 14 Languages Abyssal, telepathy 120 ft. Challenge 10 (5900 XP) Magic Resistance. The cerebrilith has advantage on saving throws against spells and other magical effects. Innate Spellcasting. The cerebrilith's spellcasting ability is Charisma (spell save DC 17). The cerebrilith can innately cast the following spells, requiring no material components: At will: detect thoughts, confusion, dissonant whispers 3/day each: darkness, dominate person, gaseous form

Actions Multiattack. The cerebrilith uses Mind Lash if it is able to. It then makes three attacks: one with its bite, and two with its claws. Bite. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 12 (2d6+5) piercing damage. Claw. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 9 (1d8+5) slashing damage. Teleport. The cerebrilith magically teleports, along with any equipment it is wearing or carrying, up to 120 feet to an unoccupied space it can see. Mind Lash (Recharge 4-6). Up to three creatures the cerebrilith can see that are within 60 feet of it each must succeed on a DC 17 Intelligence saving throw or take 17 (5d6) psychic damage. A creature that fails its save by 5 or more is also stunned until the end of its next turn.

Cerebriliths are psionic demons who seek to kill, and then consume the brains of, moral creatures. They also use their powers of mental domination to control communities of mortals to serve them, or simply to manipulate them according to the whims of their Abyssal masters. When not serving other demons, they are found in groups of up to four. They stand around 8 feet tall.

Originally from the Expanded Psionics Handbook

Lesser Spawn of Juiblex Large ooze, chaotic evil Armor Class 12 (natural armor) Hit Points 123 (13d10 + 52) Speed 40 ft., climb 30 ft. Str 20, Dex 12, Con 19, Int 4, Wis 13, Cha 10 Saving Throws Con +7, Wis +4 Damage Immunities acid, poison Damage Resistances bludgeoning, piercing, and slashing from nonmagical attacks Condition Immunities blinded, charmed, deafened, exhaustion, frightened, poisoned, prone Senses blindsight 60 ft. passive Perception 11 Languages Aquan Challenge 6 (2300 XP) Amorphous. The spawn of Juiblex can move through a space as narrow as 1 inch wide without squeezing. Sludge Form. The spawn of Juiblex ignores the effects of difficult terrain. When it moves, it can enter other creatures' spaces. A creature whose space it enters for the first time in a turn must succeed on a DC 15 Constitution saving throw or take 7 (2d6) poison damage and be poisoned until the end of the creature's next turn. Actions Multiattack. The spawn of Juiblex makes two slam attacks. Slam. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 14 (2d8+5) bludgeoning damage and the target must succeed on a DC 15 Dexterity saving throw or be coated in slime. A creature that is coated in slime takes 4 (1d8) acid damage at the start of each of its turns. On its turn, the spawn of Juiblex can make one or both of its slam attacks as if it were in the space of a creature coated in slime. A creature coated in slime can remove the slime from itself by using an action on its turn to make a DC 15 Dexterity saving throw. If a creature coated in slime is dealt 10 or more cold or fire damage, the slime is destroyed and the effect ends for that creature.

Greater Spawn of Juiblex Huge ooze, chaotic evil Armor Class 12 (natural armor) Hit Points 172 (15d12 + 75) Speed 40 ft., climb 30 ft. Str 23, Dex 10, Con 21, Int 6, Wis 15, Cha 10 Saving Throws Con +9, Wis +6 Damage Immunities acid, poison Damage Resistances bludgeoning, piercing, and slashing from nonmagical attacks Condition Immunities blinded, charmed, deafened, exhaustion, frightened, poisoned, prone Senses blindsight 60 ft. passive Perception 12 Languages Aquan Challenge 10 (5900 XP) Amorphous. The spawn of Juiblex can move through a space as narrow as 1 inch wide without squeezing. Horrific Presence. Whenever a creature starts its turn within 5 feet of the spawn of Juiblex, it must make a DC 17 Wisdom saving throw. On a success, the creature becomes immune to the Horrifying Presence of all spawn of Juiblex for 24 hours. On a failed save, the creature becomes frightened until it moves at least 10 feet away from the spawn of Juiblex. Sludge Form. The spawn of Juiblex ignores the effects of difficult terrain. When it moves, it can enter other creatures' spaces. A creature whose space it enters for the first time in a turn must succeed on a DC 17 Constitution saving throw or take 10 (3d6) poison damage and be poisoned until the end of the creature's next turn. Actions Multiattack. The spawn of Juiblex makes two melee attacks or two ranged attacks. Slam. Melee Weapon Attack: +10 to hit, reach 5 ft., one target. Hit: 19 (3d8+6) bludgeoning damage and the target must succeed on a DC 17 Dexterity saving throw or be coated in slime. A creature that is coated in slime takes 9 (2d8) acid damage at the start of each of its turns. On its turn, the spawn of Juiblex can make one or both of its slam attacks as if it were in the space of a creature coated in slime. A creature coated in slime can remove the slime from itself by using an action on its turn to make a DC 17 Dexterity saving throw. If a creature coated in slime is dealt 10 or more cold or fire damage, the slime is destroyed and the effect ends for that creature. Sludge Orb. Ranged Weapon Attack: +10 to hit, range 20/60 ft., one target. Hit: 17 (5d6) acid damage.

Elder Spawn of Juiblex Gargantuan ooze, chaotic evil Armor Class 13 (natural armor) Hit Points 214 (13d20 + 78) Speed 40 ft., climb 30 ft. Str 26, Dex 8, Con 23, Int 8, Wis 15, Cha 12 Saving Throws Con +11, Wis +7 Damage Immunities acid, poison Damage Resistances bludgeoning, piercing, and slashing from nonmagical attacks Condition Immunities blinded, charmed, deafened, exhaustion, frightened, poisoned, prone Senses blindsight 60 ft. passive Perception 12 Languages Aquan Challenge 14 (11500 XP) Amorphous. The spawn of Juiblex can move through a space as narrow as 1 inch wide without squeezing. Horrific Presence. Whenever a creature starts its turn within 5 feet of the spawn of Juiblex, it must make a DC 19 Wisdom saving throw. On a success, the creature becomes immune to the Horrifying Presence of all spawn of Juiblex for 24 hours. On a failed save, the creature becomes frightened until it moves at least 10 feet away from the spawn of Juiblex. Sludge Form. The spawn of Juiblex ignores the effects of difficult terrain. When it moves, it can enter other creatures' spaces. A creature whose space it enters for the first time in a turn must make a DC 19 Constitution saving throw. On a failed save, the creature takes 21 (6d6) poison damage, is poisoned until the end of the its next turn, and must succeed on a DC 21 Strength saving throw or be knocked prone. Actions Multiattack. The spawn of Juiblex makes two melee attacks or two ranged attacks. Slam. Melee Weapon Attack: +13 to hit, reach 10 ft., one target. Hit: 26 (4d8+8) bludgeoning damage and the target must succeed on a DC 19 Dexterity saving throw or be coated in slime. A creature that is coated in slime takes 13 (3d8) acid damage at the start of each of its turns. On its turn, the spawn of Juiblex can make one or both of its slam attacks as if it were in the space of a creature coated in slime. A creature coated in slime can remove the slime from itself by using an action on its turn to make a DC 19 Dexterity saving throw. If a creature coated in slime is dealt 10 or more cold or fire damage, the slime is destroyed and the effect ends for that creature. Sludge Orb. Ranged Weapon Attack: +13 to hit, range 30/90 ft., one target. Hit: 21 (6d6) acid damage.

The spawn of Juiblex are disgusting slime creatures who serve the Faceless Lord in a variety of capacities. Sometimes they are gifted as companions and soldiers to his most faithful thralls, other times they are sent as assassins, or simply lurk forgotten in particularly-tainted ruins. Wherever they go, they leave a path of destruction, as they consume and corrupt everything in their path, growing and bloating until they split into new spawns, or grow greater and more powerful. Lesser spawn of Juiblex are around 10 feet in diameter and weigh one-and-a-half tons. Greater spawn are around 20 feet in diameter and weigh ten tons. Elder spawn are around 40 feet in diameter and weigh almost sixty tons. 

Originally from the Monster Manual V

Glassdust Hulk Large construct, unaligned Armor Class 16 (natural armor) Hit Points 152 (16d10 + 64) Speed 30 ft. Str 22, Dex 11, Con 19, Int 3, Wis 11, Cha 2 Damage Immunities fire, poison, psychic; bludgeoning, piercing, and slashing from nonmagical attacks that aren't adamantine Damage Vulnerabilities thunder Condition Immunities charmed, exhaustion, frightened, paralyzed, petrified, poisoned Senses darkvision 120 ft. passive Perception 10 Languages understands the languages of its creator but can't speak Challenge 10 (5900 XP) Immutable Form. The glassdust hulk is immune to any spell or effect that would alter its form. Magic Resistance. The glassdust hulk has advantage on saving throws against spells and other magical effects. Magic Weapons. The glassdust hulk's weapon attacks are magical. Actions Multiattack. The glassdust hulk makes two slam attacks. Slam. Melee Weapon Attack: +10 to hit, reach 5 ft., one target. Hit: 15 (2d8+6) bludgeoning damage plus 4 (1d8) piercing damage. If the glassdust hulk scores a critical hit, and the target is a creature other than an undead or construct, the target must succeed on a DC 16 Constitution saving throw or lose 3 (1d6) hit points at the start of each of its turns due to a bleeding wound. Each time the glassdust hulk hits the wounded target with this attack, the damage dealt by the wound increases by 3 (1d6). Any creature can take an action to stanch the wound with a successful DC 16 Wisdom (Medicine) check. The wound also closes if the target receives magical healing. Shard Storm (Recharge 6). The glassdust hulk conjures a storm of glass shards. When it does, each creature within 30 feet of it must make a DC 16 Dexterity saving throw. On a failed save, a creature takes 35 (10d6) slashing damage and is blinded for 1 minute. On a successful save, a creature takes half as much damage and isn't blinded. A blinded creature may make a DC 16 Constitution saving throw at the end of each of its turns, ending the effect for itself on a success. Reactions Barbed Backswipe. Whenever a creature within 5 feet of the glassdust hulk misses it with a melee attack, the glassdust hulk can use its reaction to force that creature to succeed on a DC 15 Dexterity saving throw or take 8 (1d4+6) slashing damage.

This construct was created by mages of Esper for reasons unknown. It’s a very effective combatant, but tends to cause quite a bit of collateral damage. They stand around 12 feet tall and weigh around 3 tons. 

Another creature from Magic the Gathering, the Shards of Alara block specifically, the Glassdust Hulk intrigued me as a monster concept, so I decided to break with my typical 3.5 monster conversions to bring you this Magic the Gathering monster, statted up for D&D 5e. Don’t worry, more 3.5 conversions are on the way!

Darkweaver Medium aberration, neutral evil Armor Class 16 (natural armor) Hit Points 143 (22d8 + 44) Speed 25 ft., climb 25 ft. Str 17, Dex 18, Con 15, Int 15, Wis 16, Cha 17 Saving Throws Con +6, Wis +7 Damage Resistances cold; bludgeoning, piercing, and slashing from nonmagical attacks Damage Vulnerabilities radiant Condition Immunities charmed, frightened Senses darkvision 120 ft. passive Perception 13 Languages Abyssal, Common, Infernal Challenge 10 (5900 XP) Shadow Jump. While in dim light or darkness, the darkweaver can teleport as a bonus action up to 60 feet to an unoccupied space it can see that is also in dim light or darkness. Shadow Shroud. The darkweaver is surrounded by swirling shadows. If the darkweaver starts its turn in dim light or darkness, the darkweaver has advantage on Dexterity (Stealth) checks and attack rolls against it have disadvantage until the start of its next turn. Shadow Strands. Areas of dim light or darkness within 60 feet of the darkweaver are magically difficult terrain. Sunlight Sensitivity. While in sunlight, the darkweaver has disadvantage on attack rolls, as well as on Wisdom (Perception) checks that rely on sight. Actions Multiattack. The darkweaver makes three attacks with its tentacles, uses Reel, and makes one attack with its bite. Bite. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 11 (2d6+4) piercing damage and 14 (4d6) necrotic damage. If the target is a creature, its Strength score is reduced by 1d4. The target dies if this reduces its Strength to 0. Otherwise, this reduction lasts until the target finishes a short or long rest. Tentacle. Melee Weapon Attack: +8 to hit, reach 20 ft., one target. Hit: 7 (1d6+4) bludgeoning damage and 7 (2d6) necrotic damage. If the target is a creature, it is grappled (escape DC 15). Until the grapple ends, the target is restrained and has disadvantage on Strength checks and Strength saving throws, and the darkweaver can’t use the same tentacle on another target. The darkweaver has eight tentacles, each of which can grapple only one target. Reel. The darkweaver pulls each creature grappled by it up to 20 feet straight toward it.

This writing mass looks a bit like a spider, with too many eyes and writhing tentacles instead of legs. They originate in the Shadowfell, but many come to the Material Plane to hunt, finding prey more plentiful there, and easier to catch. They often ally with other carnivores by feeding prey they trap to such creatures to build trust, eventually gaining the affection of such creatures. Often tribes of creatures, particularly trolls, to worship a darkweaver for its shadow powers, and help it in accomplishing its dark pursuits, which vary from one individual to another. Darkweavers are 4 to 5 feet tall and weigh around 250 pounds. 

Originally from the Fiend Folio

Abyssal Ghoul Medium undead, chaotic evil Armor Class 17 (natural armor) Hit Points 136 (16d8 + 64) Speed 40 ft. Str 21, Dex 16, Con 18, Int 14, Wis 15, Cha 18 Skills Stealth +11 Damage Immunities electricity, poison Damage Resistances acid, cold, fire Condition Immunities poisoned Senses blindsight 90 ft. passive Perception 12 Languages Abyssal Challenge 10 (5900 XP) Magic Resistance. The abyssal ghoul has advantage on saving throws against spells and other magical effects. Sneak Attack (1/Turn). The abyssal ghoul deals an extra 17 (5d6) damage when it hits a target with a weapon attack and has advantage on the attack roll, or when the target is within 5 feet of an ally of the abyssal ghoul that isn't incapacitated and the abyssal ghoul doesn't have disadvantage on the attack roll. Actions Multiattack. The abyssal ghoul can use its Smoky Tongue. It then makes three attacks: two with its claws, and one with its talons. Claw. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 9 (1d8+5) slashing damage plus 9 (2d8) necrotic damage, and the target is grappled (escape DC 17). Until this grapple ends, the target is restrained, and the abyssal ghoul can't use the same claw to attack another target. Talons. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 12 (2d6+5) slashing damage plus 7 (2d6) necrotic damage. If the target is a creature, it must succeed on a DC 16 Constitution saving throw or contract a disease. Until the disease is cured, the target can't regain hit points except by magical means, and the target's hit point maximum decreases by 3 (1d6) every 24 hours. If the target's hit point maximum drops to 0 as a result of this disease, the target dies. If the target succeds on its saving throw, it is immune to contracting the disease for 24 hours. Smoky Tongue. One creature grappled by the abyssal ghoul must succeed on a DC 16 Wisdom saving throw or take 28 (8d6) psychic damage. Reactions Uncanny Dodge. The abyssal ghoul halves the damage that it takes from an attack that hits it. The abyssal ghoul must be able to see the attacker.

Humanoid, but with bizarre and twisted proportions, the abyssal ghoul looks much like a normal ghoul, but with some clearly demonic features. With scaly flesh, and a tongue trailing sickly smoke, these creatures hunt in deep caves of the Material Plane as well as part of the Abyss. In groups, they seek to outflank their opponents, attacking one target so as to distract it and make use of their sneak attack abilities. Abyssal ghouls are about the same height and weight as an adult human. 

Originally from the Fiend Folio. An anonymous request. 

Dunewinder Huge monstrosity, unaligned Armor Class 16 (natural armor) Hit Points 178 (17d12 + 68) Speed 50 ft., burrow 20 ft. Str 23, Dex 15, Con 19, Int 5, Wis 12, Cha 11 Damage Immunities fire Damage Resistances necrotic, poison Damage Vulnerabilities cold Condition Immunities blinded, prone Senses tremorsense 60 ft. passive Perception 11 Languages - Challenge 10 (5900 XP) Death Throes. When the dunewinder dies, it explodes, and each creature within 60 feet of it must make a DC 16 Dexterity saving throw, taking 17 (5d6) piercing damage and 17 (5d6) poison damage on a failed save, or half as much damage on a successful one.  Actions Bite. Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: 22 (3d10+6) piercing damage. The target must make a DC 16 Constitution saving throw, taking 42 (12d6) poison damage on a failed save, or half as much damage on a successful one. The target is grappled (escape DC 18). Until this grapple ends, the target is restrained, and the dunewinder can't use its bite on another target. Fire Breath (Recharges After A Short Or Long Rest). The dunewinder exhales fire in a 60-foot line that is 10 feet wide. Each creature in that line must make a DC 16 Dexterity saving throw, taking 49 (14d6) fire damage on a failed save, or half as much damage on a successful one.

The desert cousins of the arctic remorhaz, dunewinders are named for their sidewinding motions as they travel through the sand. They prefer to weaken prey with a blast of their fire breath, before biting and strangling them to finish them off. Often, they lie in ambush just over the crest of a dune, waiting for prey to approach. These creatures are always encounters alone. Dunewinders can be up to 40 feet long.

Originally from Sandstorm

For a compilation of all of the monster stats so far posted here, visit this Pastebin link: https://pastebin.com/raw/YtEQ4LMA

Thrym Hound Huge monstrosity, neutral evil Armor Class 17 (natural armor) Hit Points 175 (13d12 + 91) Speed 40 ft. Str 24, Dex 12, Con 25, Int 4, Wis 18, Cha 15 Damage Resistances cold Senses passive Perception 14 Languages Common, Draconic, Giant Challenge 10 (5900 XP) Keen Smell. The Thrym hound has advantage on Wisdom (Perception) checks that rely on smell. Ice-Spiked Hide. A creature that touches the Thrym hound or hits it with a melee attack while within 5 feet of it takes 2 (1d4) cold damage. Actions Multiattack. The Thrym hound makes one bite attack and two claw attacks. Bite. Melee Weapon Attack: +11 to hit, reach 10 ft., one target. Hit: 17 (3d6+7) piercing damage plus 3 (1d6) cold damage. Claw. Melee Weapon Attack: +11 to hit, reach 5 ft., one target. Hit: 14 (2d6+7) slashing damage plus 3 (1d6) cold damage. Frigid Stare (Recharge 5-6). The Thrym hound's eyes project bitter cold in a 60 foot line, 10 feet wide. Each creature in that area must make a DC 17 Dexterity saving throw, taking 45 (13d6) cold damage on a failed save, or half as much damage on a successful one. A creature that fails its save also has its speed halved until the end of its next turn.

These predators of the frozen waste are said to be a gift from the frost giant god  Thrym. Whether true or not, Thrym hounds are commonly kept as pets and warbeasts by the frost giants; though, they are also commonly encountered in the wild, sometimes alone, sometimes in packs. They sit comfortably at the top of the food chain, fearing only white dragons. Requiring only one large meal a year, these creatures often spend much of their time in the ice caves they make their lairs in. They do not keep treasure themselves, but it can often be found in their lairs among the bones of their victims. Thrym hounds stand around 12 feet tall, are around 30 feet long, and weigh approximately 15 tons.

Originally from the Monster Manual V.

Adaru Medium fiend (demon), chaotic evil Armor Class 16 (natural armor) Hit Points 110 (13d8 + 52) Speed 50 ft., burrow 20 ft., climb 30 ft. Str 17, Dex 14, Con 19, Int 16, Wis 13, Cha 18 Saving Throws Dex +6, Con +8, Wis +5 Skills Deception +8, Stealth +6 Damage Immunities poison Damage Resistances cold, fire, lightning; bludgeoning, piercing, and slashing from nonmagical attacks Condition Immunities poisoned Senses darkvision 120 ft. passive Perception 11 Languages Abyssal, telepathy 120 ft. Challenge 10 (5900 XP) Fetid Mist. A 30-foot radius cloud of vile mist surrounds the adaru. The gas spreads around corners, and its area counts as difficult terrain. Creatures that aren't demons have disadvantage on attack rolls and saving throws made while they are within the cloud, and creatures that are demons have advantage on attack rolls and saving throws made while they are within the cloud. A wind of moderate or greater speed (at least 10 miles per hour) disperses it. Magic Resistance. The adaru has advantage on saving throws against spells and other magical effects. Magic Weapons. The adaru's weapon attacks are magical. Slippery Form. The adaru has advantage on Strength (Athletics) checks made to escape a grapple. Actions Multiattack. The adaru makes two bite attacks. Bite. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 7 (1d8+3) piercing damage. The target must make a DC 16 Constitution saving throw, taking 33 (6d10) poison damage on a failed save, or half as much damage on a successful one. A creature that fails its save is also poisoned for 1 hour. Charm Demons (3/Day). The adaru chooses up to three demons within 30 feet of it that it can see. Each of those demons must succeed on a DC 16 Wisdom saving throw or become charmed by the adaru. While charmed, the demons follow the adaru's commands, which it issues telepathically (no action required). A charmed demon may repeat the saving throw each hour or whenever it takes damage. On a successful save, the effect ends for that creature.

The fluid movement of these crawling demons is almost mesmerizing. All but impossible to pin down, adarus are rarely encountered alone. They almost always have a small cadre of demons accompanying them for protection. Said to be birthed from the souls of those who lied to great consequence, adarus use subterfuge to overcome what they lack in pure brutish strength. They also enjoy feasting on their victims, and collecting body parts that they do not have. They also collect plenty of treasure to supplement their grisly trophies. Adarus are around 8 feet long and weigh about 250 pounds. 

Originally from the Monster Manual V.  If there is a monster from 3.5 or Pathfinder that you want to see converted to 5e, feel free to send me a message or submit a monster request on the submit page. I have gotten to many requests, many are works in progress and are completed but simply need workshopping before release.

Spellweaver Medium monstrosity, true neutral Armor Class 15 (natural armor) Hit Points 97 (15d8 + 30) Speed 30 ft. Str 9, Dex 16, Con 15, Int 18, Wis 17, Cha 16 Saving Throws Dex +7, Wis +7, Cha +7 Skills Arcana +8, Perception +7 Damage Resistances bludgeoning, piercing, and slashing from nonmagical attacks; psychic Condition Immunities charmed, frightened Senses passive Perception 17, truesight 120 ft. Languages can communicate telepathically with all other spellweavers within 1,000 miles, but can't speak Challenge 10 (5900 XP) Chromatic Disk (3/Day). The spellweaver is constantly accompanied by a floating magical disk that stores spell energy. While holding this disk, the spellweaver can use a bonus action to recover an expended spell slot of any level it is able to cast. The chromatic disk remains within 1 foot of the spellweaver no matter how it moves or travels. Magic Resistance. The spellweaver has advantage on saving throws against spells and other magical effects. Shielded Mind. The spellweaver is immune to magic that allows other creatures to read its thoughts, determine whether it is lying, know its alignment, or know its creature type. A creature can telepathically communicate with the spellweaver only if the spellweaver allows it to. Spellcasting. The spellweaver is a 9th-level spellcaster. Its spellcasting ability is Intelligence (spell save DC 16, +8 to hit with spell attacks). The spellweaver has the following wizard spells prepared: Cantrips (at will): firebolt, light, mage hand, mending 1st level (4 slots): alarm, detect magic, identify, magic missile 2nd level (3 slots): alter self, blur, hold person, scorching ray 3rd level (3 slots): counterspell, dispel magic, major image 4th level (3 slots): greater invisibility, wall of fire 5th level (1 slots): cloudkill, scrying Actions Multiattack. The spellweaver makes two slam attacks. Slam. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 5 (1d4+3) bludgeoning damage. Spell Weaving. The spellweaver casts a number of spells of 1st level or higher whose total spell level is no more than six, expending spell slots for each as normal. The spellweaver chooses the order in which these spells are cast. All of the spells are cast as part of one action. The spellweaver resolves each spell before deciding which spell to cast next.

These slender, mysterious creatures gather in small cabals, and are most commonly encountered while they search for magic items to add to their collection. However, solitary spellweavers are even more common. In groups, they plan and execute raids to steal magic items they desire, using scrying to scout out their foe, then attacking while invisible. They only communicate with each other telepathically, but sometimes they leave written notes behind for others to find. However, these notes are entirely incomprehensible, either gibberish or else nonsensical. Spellweavers stand around 5 feet tall and weigh around 120 pounds. 

Originally from the Monster Manual II.  An anonymous request. If there is a monster from 3.5 or Pathfinder that you want to see converted to 5e, feel free to send me a message or submit a monster request on the submit page.

Shrieking Terror Medium aberration, neutral evil Armor Class 18 (natural armor) Hit Points 97 (15d8 + 30) Speed 5 ft., fly 40 ft. Str 13, Dex 18, Con 15, Int 5, Wis 12, Cha 8 Damage Immunities poison Damage Resistances cold, fire, lightning Condition Immunities prone, poisoned Senses darkvision 60 ft. passive Perception 11 Languages Infernal Challenge 10 (5900 XP) Multiple Heads. The shrieking terror has five heads. While it has more than one head, the shrieking terror has advantage on saving throws against being blinded, charmed, deafened, frightened, stunned, and knocked unconscious. Whenever the shrieking terror takes 25 or more damage in a single turn, one of its heads dies. If all its heads die, the shrieking terror dies. At the end of its turn, it grows two heads for each of its heads that died since its last turn, unless it has taken fire damage since its last turn. The shrieking terror regains 5 hit points for each head regrown in this way. If the shrieking terror has more than five heads, the extra heads wither and die after 1 hour. The shrieking terror cannot have more than ten heads at any time. Actions Multiattack. The shrieking terror uses its Shriek if it is able to. It then makes five bite attacks. Bite. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 7 (1d6+4) piercing damage plus 10 (3d6) poison damage. The target must succeed on a DC 15 Constitution saving throw or its hit point maximum is reduced by an amount equal to the damage taken. This reduction lasts until the target finishes a long rest. Shriek (Recharge 6). The shrieking terror lets out a horrifying shriek. Each humanoid and beast within 60 feet of the shrieking terror and able to hear it must succeed on a DC 15 Wisdom saving throw or be frightened of the shrieking terror for 1 minute. If the saving throw fails by 5 or more, the target is also stunned while frightened in this way.The target may repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a target’s saving throw is successful or the effect ends for it, the target is immune to the Shriek of all shrieking terrors for 1 hour. Kiss. The shrieking terror kisses up to five incapacitated humanoids within 5 feet of it. Each target must succeed on a DC 14 Charisma saving throw or become cursed. A cursed target loses 1 point of Charisma after each hour, as its head takes on fiendish aspects. The curse doesn’t advance while the target is in sunlight or the area of a daylight spell; don’t count that time. When the cursed target’s Charisma becomes 2, it dies, and its head tears from its body and becomes a vargouille. Casting remove curse, greater restoration, or a similar spell on the target before the transformation is complete can end the curse. Doing so undoes the changes made to the target by the curse.

Formed from a fusion of hydras and vargouilles, shrieking terrors share aspects of both creatures. They were bred for war on Carceri but can be found on other planes as well. Some vargouilles revere shrieking terrors, others attack them, seeing them as perversions of vargouille-kind. Shrieking terrors have a wingspan of roughly 8 feet and weigh about 200 pounds. Though rare, sightings of ten-headed terrors have been reported.

Originally from the Monster Manual III.  If there is a monster from 3.5 or Pathfinder that you want to see converted to 5e, feel free to send me a message or submit a monster request on the submit page. I have gotten to many requests, many are works in progress and are completed but simply need workshopping before release. 

Bronze Serpent Huge construct, unaligned Armor Class 18 (natural armor) Hit Points 114 (12d12 + 36) Speed 50 ft., burrow 30 ft., climb 20 ft. Str 21, Dex 19, Con 17, Int 3, Wis 13, Cha 3 Damage Immunities lightning, poison, psychic Condition Immunities charmed, exhaustion, frightened, paralyzed, petrified, poisoned, stunned Senses darkvision 120 ft. passive Perception 11 Languages understands the languages of its creator but can’t speak Challenge 10 (5900 XP) Lightning Absorption. Whenever the bronze serpent is subjected to lightning damage, it takes no damage and instead regains a number of hit points equal to the lightning damage dealt. Magic Resistance. The bronze serpent has advantage on saving throws against spells and other magical effects. Tunneler. The bronze serpent can burrow through solid rock at half its burrow speed and leaves a 10-foot-diameter tunnel in its wake. Actions Multiattack. The bronze serpent makes two bite attacks. Bite. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 14 (2d8+5) piercing damage plus 17 (5d6) lightning damage. If the target is a creature, it must succeed on a DC 15 Constitution saving throw or be stunned until the start of its next turn. If the target has resistance to lightning damage, the target has advantage on its save. If the target has immunity to lightning damage, it automatically succeeds on its save.

Created to guard ancient snake god temples, bronze serpents are golem-like guardians over twenty feet long. Their eyes and mouth glow blue, and sparks drip from their fangs rather than venom. A bronze serpent weighs around one thousand pounds. 

Originally from the Monster Manual II. An anonymous request. If there is a monster from 3.5 or Pathfinder that you want to see converted to 5e, feel free to send me a message or submit a monster request on the submit page.

Mooncalf Large aberration, neutral evil Armor Class 15 (natural armor) Hit Points 187 (15d10 + 105) Speed 40 ft., fly 80 ft. Str 18, Dex 16, Con 24, Int 19, Wis 19, Cha 11 Skills Perception +8, Stealth +7 Damage Resistances bludgeoning, piercing and slashing damage from nonmagical attacks Senses blindsight 100 ft., passive Perception 18 Languages telepathy 120 ft. Challenge 10 (5900 XP) Innate Spellcasting. The mooncalf's spellcasting ability is Wisdom (spell save DC 16). The mooncalf can innately cast the following spells, requiring no material components: At will: call lightning 1/day each: control weather, dominate beast Actions Multiattack. The mooncalf can use Constrict. It then makes two tentacle attacks. Tentacle. Melee Weapon Attack: +8 to hit, reach 20 ft., one target. Hit: 17 (3d8+4) bludgeoning damage. If the target is a Large or smaller creature, it is grappled (escape DC 16). Until this grapple ends, the target is restrained. The mooncalf has two tentacles, each of which can grapple only one target. Constrict. The mooncalf deals 31 (6d8+4) bludgeoning damage to each creature grappled by it.

Mooncalves are said to hail from the dark side of the moon, flying down to our world to attack travelers on the peaks of mountains and tops of towers. A bat-like creature with two huge, dangling tentacles, mooncalves like to snatch prey, strangle it to death, then fly off to eat it at their leisure. The origins of their strange magical capabilities are unknown, as is much else about them. It has a wingspan of around 30 feet, and weighs around 400 pounds.

Originally from the Monster Manual II. If there is a monster from 3.5 or Pathfinder that you want to see converted to 5e, feel free to send me a message or submit a monster request on the submit page.

Happy Holidays to all of my followers!

Bluespawn Godslayer Huge monstrosity (dragonblood), lawful evil Armor Class 14 (natural armor, shield) Hit Points 162 (12d12 + 84) Speed 30 ft. Str 25, Dex 6, Con 25, Int 8, Wis 11, Cha 10 Damage Immunities lightning Condition Immunities paralyzed, unconscious Senses darkvision 60 ft. passive Perception 10 Languages Draconic Challenge 10 (5900 XP) Awesome Blow. Before making a melee attack, the bluespawn godslayer may choose to gain disadvantage on that attack. If it does, and that attack deals damage, the target must succeed on a DC 17 Strength saving throw or be knocked 10 feet away from the bluespawn godslayer in a direction it chooses. Dragonslayer. The bluespawn godslayer has advantage on attack rolls made against dragons or creatures with the dragonblood subtype. Magic Resistance. The bluespawn godslayer has advantage on saving throws against spells and other magical effects. Actions Multiattack. The bluespawn godslayer makes three attacks: two with its sword and one with its bite. Sword. Melee Weapon Attack: +11 to hit, reach 10 ft., one target. Hit: 20 (3d8+7) slashing damage plus 7 (2d6) lightning damage. Bite. Melee Weapon Attack: +11 to hit, reach 10 ft., one target. Hit: 14 (2d6+7) piercing damage plus 7 (2d6) lightning damage.

Bluespawn godslayers are among Tiamat’s most powerful soldiers. Trained specifically to kill dragons, godslayers are dull-witted but deadly, and the birth of one is seen as a great omen, and they are often abandoned by their mothers, left to solitary lives until found and recruited by the armies of Tiamat.

Originally from the Monster Manual IV.  If there is a monster from 3.5 or Pathfinder that you want to see converted to 5e, feel free to send me a message or submit a monster request on the submit page.