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

Whenever the abomination takes 25 or more damage in a single turn, a random one of its heads 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 abomination regains 10 hit points for each head regrown in this way. The regrown heads are the same type as the head lost.

If the abomination has multiple of each type of head, each head's ability has its own recharge roll. For example, if the abomination has two dragon heads, they may both use and recharge their fire breath ability independently of each other.

If, at the start of its turn, the abomination has no heads, it must make a DC 18 Constitution saving throw or be stunned until the start of its next turn. If it makes the saving throw, it has a 50% chance to regrow one head at random.

While it has less than 3 heads, for each minute that goes by where the abomination takes no damage, it will regrow 1 head type it doesn't already have. This stops once it has 3 heads, 1 of each type.

Reactive Heads. For each head the abomination has beyond one, it gets an extra reaction that can be used only for opportunity attacks. These opportunity attacks may be any melee weapon attack available to the abomination at the time.

Corrosive/Petrifying Blood. A creature that deals piercing or slashing damage while within 5 feet of the abomination takes 4 (1d8) acid damage. Additionally, their armour (if they are wearing non-magical armour) suffers a permanent and cumulative -1 penalty to armour class. If the penalty drops to either -5, or otherwise low enough that the armour is no longer providing a boost to AC, the armour is destroyed. In addition, the creature must make a DC 12 Constitution saving throw. If the saving throw fails by 5 or more, the creature is instantly petrified. Otherwise, a creature that fails the save begins to turn to stone and is restrained. The restrained creature must repeat the saving throw at the end of its next turn, becoming petrified on a failure or ending the effect on a success. The petrification lasts until the creature is freed by the greater restoration spell or other magic.

Clumsy. The abomination is unable to take the dash or disengage action due to its unnatural anatomy. In addition, if it is prone, it must expend all of its movement to stand up.

Multiattack. Up to three of the abomination's heads make one attack each. Instead of a normal attack, they may use their special ability. If the abomination has more than one of any particular type of head, that head type may make multiple attacks. Alternatively, the abomination may make two slam attacks, foregoing any attacks with its heads.

Dragon Head, Fire Breath (Recharge 5-6). The dragon head exhales fire in a 15-foot cone. Each creature in that area must make a DC 15 Dexterity saving throw, taking 31 (7d8) fire damage on a failed save, or half as much damage on a successful one.

Goat Head, Web Spit (Recharge 5-6). Ranged Weapon Attack: +8 to hit, reach 30/60 ft., one large or smaller creature. The creature is restrained by webbing. As an action, the restrained creature can make a DC 11 Strength check, escaping from the webbing on a success. The effect also ends if the webbing is destroyed. The webbing has AC 10, 5 hit points, vulnerability to fire damage, and immunity to bludgeoning, poison, and psychic damage.

Lion Head, Tentacle. Melee Weapon Attack: +8 to hit, reach 10 ft., one creature. Hit: 7 (1d10+2) piercing damage and the target must succeed on a DC 11 Constitution saving throw or be poisoned for 1 minute. The poisoned target is paralyzed, and it can repeat the saving throw at the end of each of its turns, ending the effect on a success. The target is also grappled (escape DC 15). If the target is Medium or smaller, it is also restrained until this grapple ends. Each lion head may only grapple one creature in this way. As part of this attack, the lion head may pull the target creature closer to the lion head which grappled it. If the abomination takes 15 slashing damage in a single turn while grappling a creature in this way, the creature is released and that head is no longer able to use this attack.

Dragon Head/Lion Head, Bite. Melee Weapon Attack: +8 to hit, reach 5 ft., one creature. Hit: 13 (2d6+6) piercing damage. If the target is a medium or smaller creature grappled by the abomination, that creature is swallowed, and the grapple ends. While swallowed, the creature is blinded and restrained, it has total cover against attacks and other effects outside the abomination, and it takes 9 (2d8) acid damage at the start of each of the abomination's turns. Additionally, a swallowed creature suffers the reduction to armour class and petrification described in the Corrosive/Petrifying Blood trait. If the abomination takes 25 or more damage in a single turn from a creature inside it, the abomination must make a DC 18 Constitution saving throw or regurgitate the swallowed creature, which falls prone within ten feet of the abomination. The abomination may only have one creature swallowed at a time. Once a creature dies inside the stomach of the abomination, it may swallow another.

Goat Head, Horns. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 12 (1d12 + 6) bludgeoning damage.

Slam. Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: 15 (2d8+6) bludgeoning damage.

Rock. Ranged Weapon Attack: +8 to hit, range 60/240 ft., one target. Hit: 28 (4d10 + 6) bludgeoning damage.