Blooming Hydra

Hold Breath. The hydra can hold its breath for 1 hour.

Multiple Heads. The hydra has five heads. While it has more than one head, the hydra has advantage on saving throws against being blinded, charmed, deafened, frightened, stunned, and knocked unconscious.

Whenever the hydra takes 25 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 10 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.

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

Legendary Resistance (3/Day)  If the hydra fails a saving throw, it can choose to succeed instead.

Multiattack. The hydra makes as many bite attacks as it has heads.

Bite. Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: 49 (18d10 + 5) piercing damage.

Neck smash (Costs two Legendary actions) With a violent sweep of it's long, serpentine necks, the hydra seeks to knock the player characters from their feet. Each player within 10 ft. of the hydra must make a DC 18 Strength saving throw or be knocked prone.

Costume Change It's hide shifting and changing, both in color and texture, the hydra makes it's flesh thick and scaly, impervious to all but the most ferocious of blows. It adds +2 to it's AC until the start of it's next turn

Tail Lash With a brutal twist of it's body, the hydra lashes out at one of the player characters with it's tail. Any player targeted with this attack must succeed a DC 18 dexterity saving throw or suffer 3d6+6 bludgeoning damage. The tail wraps itself around the player and holds them in place, restraining them until they wrestle free. Requiring a DC 18 Strength saving throw.

Drag and Drop Seizing a player in one of it's mouths, the hydra lifts the struggling victim into the air before smashing them into the earth. The hydra makes a Bite attack on one player. If successful, the hydra has seized their prey; the player must make a DC 17 saving throw to try and wrestle free. Should they fail, the hydra brings the player smashing into the earth and then throwing the player at another player, the hydra rolls to hit. If successful they both suffer 3d6+3 bludgeoning damage from the fall and are left prone, on a miss the player is just slammed and left on the ground.

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

The hydra can take three 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. Spent Legendary Actions are regained at the start of each turn

Costume Change It's hide shifting and changing, both in color and texture, the hydra makes it's flesh thick and scaly, impervious to all but the most ferocious of blows. It adds +2 to it's AC until the start of it's next turn

Multiattack (Costs two Legendary Actions) The hydra makes a Multiattack.

Neck smash (Costs two Legendary actions) With a violent sweep of it's long, serpentine necks, the hydra seeks to knock the players from their feet. Each player within 10 ft. of the hydra must make a DC 18 Strength saving throw or be knocked prone.