Yiildragoth
Huge • Aberration • Lawful Evil
Armor Class 17
Hit Points 230 (20d12 + 100)
Speed 20 ft., swim 40 ft.
Initiative -1 (9)
| STR | DEX | CON | INT | WIS | CHA |
|---|---|---|---|---|---|
| 22 (+6) | 8 (-1) | 20 (+5) | 18 (+4) | 17 (+3) | 19 (+4) |
Saving Throws Str +11, Int +9
Skills History +14, Insight +8, Perception +8, Deception +9
Damage Resistances acid, psychic
Senses blindsight 20 ft., darkvision 120 ft., passive Perception 18
Languages Deep Speech, telepathy 120 ft.
CR 14 (XP 11,500 or 13,000 in lair; PB +5)
Amphibious. The yiildragoth can breathe air and water.
Creature Sense. The yiildragoth is aware of creatures within 100 feet of it that have an Intelligence score of 4 or higher. It knows the distance and direction to each creature, as well as each one's Intelligence score, but can't sense anything else about it. A creature protected by a mind blank spell, a nondetection spell, or similar magic can't be perceived in this manner.
Paced Resistance (1/Day; 2/Day in Lair). If the yiildragoth fails a saving throw, it can choose to succeed instead. For each time the yiildragoth used this ability, it loses one of its Legendary Actions per round until it finishes a long rest.
Magic Resistance. The yiildragoth has advantage on saving throws against spells and other magical effects.
ACTIONS
Bite. Melee Weapon Attack: +11, reach 15 ft. Hit: 32 (4d12 + 6) piercing damage plus 16 (3d10) acid damage.
Befuddling Breath (Recharge 5-6). Wisdom Saving Throw: DC 18, each creature in a 60-foot cone. Failure: 36 (8d8) psychic damage, and the target has disadvantage on Intelligence, Wisdom, and Charisma saving throws until the end of its next turn. Success: Half damage.
BONUS ACTIONS
Shell Defense. The yiildragoth withdraws into its shell. Until it emerges, it gains a +7 bonus to its AC, is restrained, and a critical hit against it becomes a normal hit. It can emerge from its shell as a bonus action on its turn.
REACTIONS
Spell Reflection. Trigger: The yiildragoth succeeds on a saving throw against a spell, or a spell's attack roll misses it. Response - Dexterity Saving Throw: DC 18, one creature the yiildragoth can see within 120 feet. Failure: 19 (3d12) force damage.
LEGENDARY ACTIONS
Legendary Action Uses: 3 (4 in Lair). Immediately after another creature's turn, the yiildragoth can expend a use to take one of the following actions. The yiildragoth regains all expended uses at the start of each of its turns.
Aberrant Wisdom. Charisma Saving Throw: DC 17, each creature in a 30-foot emanation originating from the yiildragoth. Failure: The target becomes affected by the feeblemind spell until the end of its next turn. Success: The target becomes immune to this effect for 24 hours. Failure or Success: The yiildragoth can’t take this action again until the start of its next turn.
Psychic Strike. Intelligence Saving Throw: DC 17, one creature within 60 feet of the yiildragoth. Failure: 11 (2d10) psychic damage. Success: Half damage.
Reverberating Shell. Wisdom Saving Throw: DC 18, each creature in a 30-foot emanation originating from the yiildragoth. Failure: The target becomes incapacitated until the end of its next turn. Success: The target becomes deafened until the end of its next turn. Failure or Success: The yiildragoth can’t take this action again until the start of its next turn.
Yiildragoth
Huge • Aberration • Lawful Evil
Armor Class 16
Hit Points 199 (19d12 + 76)
Speed 20 ft., swim 40 ft.
Initiative -1 (9)
| STR | DEX | CON | INT | WIS | CHA |
|---|---|---|---|---|---|
| 20 (+5) | 8 (-1) | 18 (+4) | 16 (+3) | 15 (+2) | 17 (+3) |
Saving Throws Str +9, Int +7
Skills History +11, Insight +6, Perception +6, Deception +7
Damage Resistances acid, psychic
Senses darkvision 120 ft., passive Perception 16
Languages Deep Speech, telepathy 120 ft.
CR 11 (XP 7.200 or 8.400 in lair; PB +4)
Amphibious. The yiildragoth can breathe air and water.
Creature Sense. The yiildragoth is aware of creatures within 100 feet of it that have an Intelligence score of 4 or higher. It knows the distance and direction to each creature, as well as each one's Intelligence score, but can't sense anything else about it. A creature protected by a mind blank spell, a nondetection spell, or similar magic can't be perceived in this manner.
Paced Resistance (1/Day; 2/Day in Lair). If the yiildragoth fails a saving throw, it can choose to succeed instead. For each time the yiildragoth used this ability, it loses one of its Legendary Actions per round until it finishes a long rest.
Magic Resistance. The yiildragoth has advantage on saving throws against spells and other magical effects.
ACTIONS
Bite. Melee Weapon Attack: +9, reach 15 ft. Hit: 24 (3d12 + 5) piercing damage plus 11 (2d10) acid damage.
Befuddling Breath (Recharge 5-6). Wisdom Saving Throw: DC 16, each creature in a 60-foot cone. Failure: 31 (7d8) psychic damage, and the target has disadvantage on Intelligence, Wisdom, and Charisma saving throws until the end of its next turn. Success: Half damage.
BONUS ACTIONS
Shell Defense. The yiildragoth withdraws into its shell. Until it emerges, it gains a +6 bonus to its AC, is restrained, and a critical hit against it becomes a normal hit. It can emerge from its shell as a bonus action on its turn.
REACTIONS
Spell Reflection. Trigger: The yiildragoth succeeds on a saving throw against a spell, or a spell's attack roll misses it. Response - Dexterity Saving Throw: DC 16, one creature the yiildragoth can see within 120 feet. Failure: 13 (2d12) force damage.
LEGENDARY ACTIONS
Legendary Action Uses: 3 (4 in Lair). Immediately after another creature's turn, the yiildragoth can expend a use to take one of the following actions. The yiildragoth regains all expended uses at the start of each of its turns.
Aberrant Wisdom. Charisma Saving Throw: DC 15, each creature in a 30-foot emanation originating from the yiildragoth. Failure: The target becomes affected by the feeblemind spell until the end of its next turn. Success: The target becomes immune to this effect for 24 hours. Failure or Success: The yiildragoth can’t take this action again until the start of its next turn.
Psychic Strike. Intelligence Saving Throw: DC 15, one creature within 60 feet of the yiildragoth. Failure: 7 (2d6) psychic damage. Success: Half damage.
Reverberating Shell. Wisdom Saving Throw: DC 16, each creature in a 30-foot emanation originating from the yiildragoth. Failure: The target becomes incapacitated until the end of its next turn. Success: The target becomes deafened until the end of its next turn. Failure or Success: The yiildragoth can’t take this action again until the start of its next turn.
Yiildragoth
Huge • Aberration • Lawful Evil
Armor Class 18
Hit Points 287 (23d12 + 138)
Speed 20 ft., swim 40 ft.
Initiative -1 (9)
| STR | DEX | CON | INT | WIS | CHA |
|---|---|---|---|---|---|
| 24 (+7) | 8 (-1) | 22 (+6) | 20 (+5) | 19 (+4) | 21 (+5) |
Saving Throws Str +13, Int +11
Skills History +17, Insight +10, Perception +10, Deception +11
Damage Resistances acid, psychic
Senses blindsight 30 ft., darkvision 120 ft., passive Perception 20
Languages Deep Speech, telepathy 120 ft.
CR 17 (XP 18.000 or 20.000 in lair; PB +6)
Amphibious. The yiildragoth can breathe air and water.
Creature Sense. The yiildragoth is aware of creatures within 300 feet of it that have an Intelligence score of 4 or higher. It knows the distance and direction to each creature, as well as each one's Intelligence score, but can't sense anything else about it. A creature protected by a mind blank spell, a nondetection spell, or similar magic can't be perceived in this manner.
Paced Resistance (1/Day; 2/Day in Lair). If the yiildragoth fails a saving throw, it can choose to succeed instead. For each time the yiildragoth used this ability, it loses one of its Legendary Actions per round until it finishes a long rest.
Magic Resistance. The yiildragoth has advantage on saving throws against spells and other magical effects.
ACTIONS
Bite. Melee Weapon Attack: +13, reach 15 ft. Hit: 39 (5d12 + 7) piercing damage plus 22 (4d10) acid damage.
Befuddling Breath (Recharge 5-6). Wisdom Saving Throw: DC 20, each creature in a 60-foot cone. Failure: 40 (9d8) psychic damage, and the target has disadvantage on Intelligence, Wisdom, and Charisma saving throws until the end of its next turn. Success: Half damage.
BONUS ACTIONS
Shell Defense. The yiildragoth withdraws into its shell. Until it emerges, it gains a +8 bonus to its AC, is restrained, and a critical hit against it becomes a normal hit. It can emerge from its shell as a bonus action on its turn.
REACTIONS
Spell Reflection. Trigger: The yiildragoth succeeds on a saving throw against a spell, or a spell's attack roll misses it. Response - Dexterity Saving Throw: DC 20, one creature the yiildragoth can see within 120 feet. Failure: 26 (4d12) force damage.
LEGENDARY ACTIONS
Legendary Action Uses: 3 (4 in Lair). Immediately after another creature's turn, the yiildragoth can expend a use to take one of the following actions. The yiildragoth regains all expended uses at the start of each of its turns.
Aberrant Wisdom. Charisma Saving Throw: DC 19, each creature in a 30-foot emanation originating from the yiildragoth. Failure: The target becomes affected by the feeblemind spell until the end of its next turn. Success: The target becomes immune to this effect for 24 hours. Failure or Success: The yiildragoth can’t take this action again until the start of its next turn.
Psychic Strike. Intelligence Saving Throw: DC 19, one creature within 60 feet of the yiildragoth. Failure: 13 (3d8) psychic damage. Success: Half damage.
Reverberating Shell. Wisdom Saving Throw: DC 20, each creature in a 30-foot emanation originating from the yiildragoth. Failure: The target becomes incapacitated until the end of its next turn. Success: The target becomes deafened until the end of its next turn. Failure or Success: The yiildragoth can’t take this action again until the start of its next turn.
QUICK REFERENCE
USING MONSTER VARIANTS
Monster variants allow the GM to adjust encounters to better match the party’s strength, narrative needs, or world-building logic. A weaker variant may represent a juvenile, wounded, or lesser specimen, while a stronger variant can serve as a leader, champion, ancient creature, or apex predator.
Variants can be used to fine-tune difficulty without changing the core identity of the monster, making them ideal for scaling encounters, reinforcing hierarchy within a faction, or creating memorable boss-style enemies. You can even use the same stat block but different variants in the same encounter if you want.
Design Note. Each monster is primarily balanced around its normal version. Weaker and stronger variants are derived adjustments and may not always preserve every tactical nuance or “feel” of the original creature. GMs are encouraged to review variants carefully and adjust abilities or tactics as needed to best suit their table.