From Pathfinder Howl of the Wild, which isn't enabled.

Greater Chimera

CREATURE 13

RARE HUGE BEAST

Perception +23; darkvision, scent (imprecise) 30 feet

Skills Acrobatics +22, Athletics +27, Stealth +27

Str +8, Dex +4, Con +5, Int -2, Wis +3, Cha +1

AC 33; Fort +26, Ref +23, Will +20

HP 235

Reactive Strike

Trigger A creature within the monster's reach uses a manipulate action or a move action, makes a ranged attack, or leaves a square during a move action it's using.

Effect The monster attempts a melee Strike against the triggering creature. If the attack is a critical hit and the trigger was a manipulate action, the monster disrupts that action. This Strike doesn't count toward the monster's multiple attack penalty, and its multiple attack penalty doesn't apply to this Strike.

Three-Headed

Any ability that would sever a greater chimera's head (such as a critical hit with a Vorpal weapon) severs one head at random. Losing a head doesn't kill a chimera (as long as it has at least one head left), but it does prevent it from making Strikes with the lost head or using any abilities granted by the head.

Speed 25 feet, fly 40 feet

Melee Claw +25 (agile, unarmed), Damage 3d8+8 slashing

Multiple Reactions

A greater chimera gains 2 extra reactions each round that it can use only to make Reactive Strikes. It must use a different head for each reaction, and it can't use more than one on the same triggering action. If it loses one of its heads, it also loses one of these extra reactions.

Three-Headed Strike

The greater chimera makes a Strike with each of its heads, each at a –2 penalty and targeting a different creature. These Strikes count as only one attack for the greater chimera's multiple attack penalty, and the penalty doesn't increase until after it has made all three attacks.

Pathfinder Howl of the WildORC