Reactive Heads. For each head the dracohydra has beyond one, it gets an extra reaction that can be used only for opportunity attacks.

Wakeful. While the dracohydra sleeps, at least one of its heads is awake.

Bite. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 9 (1d10 + 4) piercing damage.

Breath Weapons (Recharge 5–6). The dragon uses one of the following breath weapons.

Cold Breath. The dragon exhales an icy blast in a 15-foot cone. Each creature in that area must make a DC 13 Constitution saving throw, taking 18 (4d8) cold damage on a failed save, or half as much damage on a successful one.

Fire Breath. The dragon exhales fire in a 15-foot cone. Each creature in that area must make a DC 13 Dexterity saving throw, taking 22 (4d10) fire damage on a failed save, or half as much damage on a successful one.

Singularity Breath. The dragon creates a shining bead of gravitational force in its mouth, then releases the energy in a 15-foot cone. Each creature in that area must make a DC 13 Strength saving throw. On a failed save, the creature takes 22 (5d8) force damage, and its speed becomes 0 until the start of the dragon’s next turn. On a successful save, the creature takes half as much damage, and its speed isn’t reduced.

Weakening Breath. The dragon exhales gas in a 15-foot cone. Each creature in that area must succeed on a DC 13 Strength saving throw or have disadvantage on Strength-based attack rolls, Strength checks, and Strength saving throws for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Paralyzing Breath. The dragon exhales paralyzing gas in a 15-foot cone. Each creature in that area must succeed on a DC 13 Constitution saving throw or be paralyzed for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.