This is homebrew, submitted by a member of the community.
Thessalhydra
Thessalhydra
Huge monstrosity, unalignedHuge monstrosity, unaligned
Actions
Multiattack. The thessalhydra makes one maw attack and one Flurry of Bites.
Flurry of Bites. Melee Weapon Attack: +7 to hit, reach 10 ft., one target. Hit: 7 (1d6+4) piercing damage plus 10 (4d4) poison damage.
Maw. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 9 (1d10+4) piercing damage plus 5 (1d10) acid damage.
Tail Pincer. Melee Weapon Attack: +7 to hit, reach 10 ft., one target. Hit: 10 (1d12+4) slashing damage, and the target is grappled. As an action, the target can escape the grapple by succeeding on a DC 14 Strength (Athletics) or Dexterity (Acrobatics) check (its choice). Until this grapple ends, the thessalhydra can't use its tail pincer.
Acid Saliva (Recharge d6: 5–6). The thessalhydra spits a glob of acid at a point it can see within 30 feet of it. Each creature within 10 feet of that point must make a DC 15 Dexterity saving throw, taking 18 (4d8) acid damage on a failed save, or half as much damage on a successful one.
[b]Multiattack.[/b] The thessalhydra makes one maw attack and one Flurry of Bites.
[b]Flurry of Bites.[/b] Melee Weapon Attack: [+7] to hit, reach 10 ft., one target. Hit: 7 ([1d6+4]) piercing damage plus 10 ([4d4]) poison damage.
[b]Maw.[/b] Melee Weapon Attack: [+7] to hit, reach 5 ft., one target. Hit: 9 ([1d10+4]) piercing damage plus 5 ([1d10]) acid damage.
[b]Tail Pincer.[/b] Melee Weapon Attack: [+7] to hit, reach 10 ft., one target. Hit: 10 ([1d12+4]) slashing damage, and the target is grappled. As an action, the target can escape the grapple by succeeding on a DC 14 Strength (Athletics) or Dexterity (Acrobatics) check (its choice). Until this grapple ends, the thessalhydra can't use its tail pincer.
[b]Acid Saliva (Recharge [d6]: 5–6).[/b] The thessalhydra spits a glob of acid at a point it can see within 30 feet of it. Each creature within 10 feet of that point must make a DC 15 Dexterity saving throw, taking 18 ([4d8]) acid damage on a failed save, or half as much damage on a successful one.
Legendary Actions
The thessalhydra can take 2 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 thessalhydra regains spent legendary actions at the start of its turn.
Detect. The thessalhydra makes a Wisdom (Perception) check with advantage.
Tail Swipe. The thessalhydra makes a tail pincer attack.
The thessalhydra can take 2 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 thessalhydra regains spent legendary actions at the start of its turn.[b]Detect.[/b] The thessalhydra makes a Wisdom (Perception) check with advantage.
[b]Tail Swipe.[/b] The thessalhydra makes a tail pincer attack.
Details
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