Manatide Hydra
Gargantuan • Monstrosity • Unaligned
Armor Class 18
Hit Points 314 (17d20 + 136)
Speed 40 ft., burrow 40 ft.
Initiative +8 (18)
| STR | DEX | CON | INT | WIS | CHA |
|---|---|---|---|---|---|
| 24 (+7) | 14 (+2) | 26 (+8) | 4 (−3) | 16 (+3) | 9 (−1) |
Saving Throws Str +13, Con +14
Skills Perception +15
Condition Immunities blinded, charmed, deafened, frightened, stunned, unconscious
Senses darkvision 120 ft., passive Perception 25
Languages –
CR 20 (XP 25,000 or 33,000 in lair; PB +6)
Magic Resistance. The hydra has advantage on saving throws against spells and other magical effects.
Multiple Heads. The hydra has six heads. Whenever the hydra takes 40 or more damage in a single turn, one of its heads dies. If all its heads die, the hydra 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 hydra regains 15 hit points for each head regrown in this way.
Reactive Heads. For each head the hydra has beyond one, it gets an extra reaction that can be used only for opportunity attacks.
ACTIONS
Multiattack. The hydra makes as many Bite attacks as it has heads. It can replace any number of Bite attacks for a use of Mana Breath, if available.
Bite. Melee Weapon Attack: +13, reach 20 ft. Hit: 14 (2d6 + 7) piercing damage.
Mana Breath (1/Day, 2/Day in Lair). Constitution Saving Throw: DC 16 + 1 for each of the hydra's heads or Bite attacks replaced, each creature in a 90-foot cone. Failure: The target rolls a d8 to determine the effect it suffers:
- The target can't speak for 1 minute. Whenever it tries, pink bubbles float out of its mouth. The target repeats the save at the ends of its turns, ending the effect on a success.
- The target becomes affected by the confusion spell for 1 minute. The target repeats the save at the ends of its turns, ending the effect on a success.
- The target is teleported into a random direction for a distance of 1d100 × 5 feet (including vertical). If it would end in an occupied space, it is shunted to the nearest unoccupied space and takes 1d6 force damage per 5 feet shunted.
- The target’s body turns translucent like glass and gains vulnerability to all damage it isn’t resistant to or immune to until the end of the hydra’s next turn.
- The target turns into a potted plant and gains 1 temporary hit point. While it has that temporary hit point, it stays and is incapacitated, has a speed of 0, and can’t speak.
- The target becomes Tiny for 1 hour, and its Strength score is halved.
- Whenever the target would restore hit points through any means in the next minute, it doesn’t regain any hit points, but instead the creature closest to it does.
- The target casts fireball (level 5, spell save DC 22) centered on itself.
REACTIONS
Dispelling Screech (Recharge 5-6). Trigger: The hydra sees a creature within 60 feet casting a spell. Response - Constitution Saving Throw: DC 22. Failure: The spell fails to take effect and is wasted.
LEGENDARY ACTIONS
Legendary Action Uses: 3 (4 in Lair). Immediately after another creature's turn, the hydra can take 3 legendary actions, choosing from the options below. Only one legendary action can be used at a time and only at the end of another creature's turn. The hydra regains spent legendary actions at the start of its turn.
Bite. The hydra makes one Bite attack.
Frenzied Flailing. Dexterity Saving Throw: DC 21, each creature in a 20-foot emanation originating from the hydra. Failure: 12 (1d10 + 7) bludgeoning damage, and the target is knocked prone. Failure or Success: The hydra can't take this action again until the start of its next turn.
Bite Off Head. The hydra bites off one of its own heads, provided it has more than one head. It then immediately regrows two heads and regains 30 hit points. The hydra can't take this action again until the start of its next turn.
Manatide Hydra
Gargantuan • Monstrosity • Unaligned
Armor Class 17
Hit Points 245 (14d20 + 98)
Speed 40 ft., burrow 40 ft.
Initiative +7 (17)
| STR | DEX | CON | INT | WIS | CHA |
|---|---|---|---|---|---|
| 22 (+6) | 12 (+1) | 24 (+7) | 4 (−3) | 14 (+2) | 9 (−1) |
Saving Throws Str +12, Con +13
Skills Perception +14
Condition Immunities blinded, charmed, deafened, frightened, stunned, unconscious
Senses darkvision 120 ft., passive Perception 24
Languages –
CR 17 (XP 18,000 or 20,000 in lair, PB +6)
Magic Resistance. The hydra has advantage on saving throws against spells and other magical effects.
Multiple Heads. The hydra has six heads. Whenever the hydra takes 40 or more damage in a single turn, one of its heads dies. If all its heads die, the hydra 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 hydra regains 15 hit points for each head regrown in this way.
Reactive Heads. For each head the hydra has beyond one, it gets an extra reaction that can be used only for opportunity attacks.
ACTIONS
Multiattack. The hydra makes as many Bite attacks as it has heads. It can replace any number of Bite attacks for a use of Mana Breath, if available.
Bite. Melee Weapon Attack: +12, reach 20 ft. Hit: 11 (1d10 + 6) piercing damage.
Mana Breath (1/Day, 2/Day in Lair). Constitution Saving Throw: DC 15 + 1 for each of the hydra's heads or Bite attacks replaced, each creature in a 90-foot cone. Failure: The target rolls a d8 to determine the effect it suffers:
- The target can't speak for 1 minute. Whenever it tries, pink bubbles float out of its mouth. The target repeats the save at the ends of its turns, ending the effect on a success.
- The target becomes affected by the confusion spell for 1 minute. The target repeats the save at the ends of its turns, ending the effect on a success.
- The target is teleported into a random direction for a distance of 1d100 × 5 feet (including vertical). If it would end in an occupied space, it is shunted to the nearest unoccupied space and takes 1d6 force damage per 5 feet shunted.
- The target’s body turns translucent like glass and gains vulnerability to all damage it isn’t resistant to or immune to until the end of the hydra’s next turn.
- The target turns into a potted plant and gains 1 temporary hit point. While it has that temporary hit point, it stays and is incapacitated, has a speed of 0, and can’t speak.
- The target becomes Tiny for 1 hour, and its Strength score is halved.
- Whenever the target would restore hit points through any means in the next minute, it doesn’t regain any hit points, but instead the creature closest to it does.
- The target casts fireball (spell save DC 21) centered on itself.
REACTIONS
Dispelling Screech (Recharge 5-6). Trigger: The hydra sees a creature within 60 feet casting a spell. Response - Constitution Saving Throw: DC 21. Failure: The spell fails to take effect and is wasted.
LEGENDARY ACTIONS
Legendary Action Uses: 3 (4 in Lair). Immediately after another creature's turn, the hydra can take 3 legendary actions, choosing from the options below. Only one legendary action can be used at a time and only at the end of another creature's turn. The hydra regains spent legendary actions at the start of its turn.
Bite. The hydra makes one Bite attack.
Frenzied Flailing. Dexterity Saving Throw: DC 20, each creature in a 20-foot emanation originating from the hydra. Failure: 9 (1d6 + 6) bludgeoning damage, and the target is knocked prone. Failure or Success: The hydra can't take this action again until the start of its next turn.
Bite Off Head. The hydra bites off one of its own heads, provided it has more than one head. It then immediately regrows two heads and regains 30 hit points. The hydra can't take this action again until the start of its next turn.
Manatide Hydra
Gargantuan • Monstrosity • Unaligned
Armor Class 19
Hit Points 390 (20d20 + 180)
Speed 40 ft., burrow 40 ft.
Initiative +10 (20)
| STR | DEX | CON | INT | WIS | CHA |
|---|---|---|---|---|---|
| 26 (+8) | 16 (+3) | 28 (+9) | 4 (−3) | 18 (+4) | 9 (−1) |
Saving Throws Str +15, Con +16
Skills Perception +18
Condition Immunities blinded, charmed, deafened, frightened, stunned, unconscious
Senses darkvision 120 ft., passive Perception 28
Languages –
CR 23 (XP 50,000 or 62,000 in lair, PB +7)
Magic Resistance. The hydra has advantage on saving throws against spells and other magical effects.
Multiple Heads. The hydra has six heads. Whenever the hydra takes 40 or more damage in a single turn, one of its heads dies. If all its heads die, the hydra 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 hydra regains 15 hit points for each head regrown in this way.
Reactive Heads. For each head the hydra has beyond one, it gets an extra reaction that can be used only for opportunity attacks.
ACTIONS
Multiattack. The hydra makes as many Bite attacks as it has heads. It can replace any number of Bite attacks for a use of Mana Breath, if available.
Bite. Melee Weapon Attack: +15, reach 20 ft. Hit: 21 (3d8 + 8) piercing damage.
Mana Breath (1/Day, 2/Day in Lair). Constitution Saving Throw: DC 17 + 1 for each of the hydra's heads or Bite attacks replaced, each creature in a 120-foot cone. Failure: The target rolls a d8 to determine the effect it suffers:
- The target can't speak for 1 minute. Whenever it tries, pink bubbles float out of its mouth. The target repeats the save at the ends of its turns, ending the effect on a success.
- The target becomes affected by the confusion spell for 1 minute. The target repeats the save at the ends of its turns, ending the effect on a success.
- The target is teleported into a random direction for a distance of 1d100 × 5 feet (including vertical). If it would end in an occupied space, it is shunted to the nearest unoccupied space and takes 1d6 force damage per 5 feet shunted.
- The target’s body turns translucent like glass and gains vulnerability to all damage it isn’t resistant to or immune to until the end of the hydra’s next turn.
- The target turns into a potted plant and gains 1 temporary hit point. While it has that temporary hit point, it stays and is incapacitated, has a speed of 0, and can’t speak.
- The target becomes Tiny for 1 hour, and its Strength score is halved.
- Whenever the target would restore hit points through any means in the next minute, it doesn’t regain any hit points, but instead the creature closest to it does.
- The target casts fireball (level 5, spell save DC 24) centered on itself.
REACTIONS
Dispelling Screech (Recharge 4-6). Trigger: The hydra sees a creature within 60 feet casting a spell. Response - Constitution Saving Throw: DC 24. Failure: The spell fails to take effect and is wasted.
LEGENDARY ACTIONS
Legendary Action Uses: 3 (4 in Lair). Immediately after another creature's turn, the hydra can take 3 legendary actions, choosing from the options below. Only one legendary action can be used at a time and only at the end of another creature's turn. The hydra regains spent legendary actions at the start of its turn.
Bite. The hydra makes one Bite attack.
Frenzied Flailing. Dexterity Saving Throw: DC 23, each creature in a 20-foot emanation originating from the hydra. Failure: 16 (2d8 + 7) bludgeoning damage, and the target is knocked prone. Failure or Success: The hydra can't take this action again until the start of its next turn.
Bite Off Head. The hydra bites off one of its own heads, provided it has more than one head. It then immediately regrows two heads and regains 30 hit points. The hydra 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.