Half-Green Dragon Hydra

Family: Hydra

Huge monstrosity

Armor Class 15 (natural armor)
Hit Points 161 (14d12 + 70)
Speed 30 ft., swim 30 ft.

20 (+5) 12 (+1) 20 (+5) 7 (-2) 10 (+0) 7 (-2)

Skills Perception +4
Damage Immunities poison
Senses passive Perception 14, blindsight 10 ft., darkvision 60 ft.
Languages Draconic
Challenge 10 (5,900 XP)
Proficiency Bonus +4


  • Amphibious. The hydra/green dragon can breathe air and water.
  • Legendary-Resistances (2/day). If the hydra/green dragon fails a saving throw, it can choose to succeed instead.
  • Multiple Heads. The hydra/green dragon has five heads. While it has more than one head, the hydra/green dragon has advantage on saving throws against being blinded, charmed, deafened, frightened, stunned, and knocked unconscious. Whenever the hydra/green dragon takes 30 or more damage in a single turn, one of its heads dies. If all its heads die, the hydra/green dragon 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/green dragon regains 10 hit points for each head regrown in this way.
  • Reactive Heads. For each head the hydra/green dragon has beyond one, it gets an extra reaction that can be used only for opportunity attacks.
  • Wakeful. While the hydra/green dragon sleeps, at least one of its heads is awake.


  • Multiattack. The hydra/green dragon makes as many bite attacks or caustic spit attacks as it has heads.
  • Bite. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 10 (1d10 + 5) piercing damage.
  • Poison Spit. Ranged Weapon Attack: +9 to hit, range 60 ft./120 ft., one target. Hit: 10 (1d10 + 5) poison damage.
  • Poison Breath (Recharge 5-6). Each of the hydra/green dragon’s heads exhales poisonous gas in a 30-foot cone. Each creature in that area must make a DC 14 Constitution saving throw, taking 10 (3d6) poison damage on a failed save, or half as much damage on a successful one.


The hydra/green dragon can take 2 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature’s turn. They regains spent legendary actions at the start of their turn.

  • Bite. The hydra/green dragon makes one bite attack.
  • Spit. The hydra/green dragon makes a spit poison attack.


This half-green dragon hydra is the source of many local legends, and countless heroes have met their end trying to vanquish it.

Section 15: Copyright Notice

Mother of Monsters False Prophecies (5e) Copyright 2023 Legendary Games. Authors Adrian Arduini, Mike Myer, Lynne M. Meyer

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