Keen Senses. Allagi has advantage on Wisdom (Perception) checks that rely on hearing or smell.

Ambusher. Allagi has advantage on Stealth checks when in dim light or darkness. Also, in the first round of combat, Allagi has advantage on attack rolls against any creature it surprised.

Pounce. If Allagi moves at least 20 feet straight toward a creature and then hits it with a claw attack on the same turn, that target must succeed on a DC l7 Strength saving throw or be knocked prone.

Shifting Attack. When Allagi makes an attack on their turn they can alter their form for the next attack, choosing one option from the Shifting Attacks list.

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

Innate Spellcasting. Allagi is an innate spellcaster. Its spellcasting ability is Wisdom (spell save DC 15). Allagi has the following spells prepared:

At Will: Freedom of Movement, Pass Without A Trace, and Polymorph (Self Only)

2/Day: Blur and Dominate Beast 

1/Day: Invisibility and Conjure Animals 

Multiattack. Allagi makes three attacks:

Standard Attacks:
Bite. Melee Weapon Attack: +12 to hit, reach 5 ft., 1 target. Hit: 11 (1d8 + 7) piercing damage. 

Claw. Melee Weapon Attack: +12 to hit, reach 10 ft., 1 target. Hit: 11 (1d8 + 7) slashing damage.

Shifting Attacks:
Smashing Antlers. Melee Weapon Attack: +12 to hit, reach 10 ft., 1 target. Hit: 11 (1d8 + 7) bludgeoning damage. When Allagi targets a creature, they make this attack against all other creatures within 5 ft. of the target as long as they are within range.

Trampling Hooves. Melee Weapon Attack: +12 to hit, reach 5 ft., 1 target. Hit: 11 (1d8 + 7) bludgeoning damage. This attack deals an extra 8 (2d8) bludgeoning damage to a target who is prone.

Vicious Fangs. Melee Weapon Attack: +12 to hit, reach 5 ft., 1 target. Hit: 11 (1d8 + 7) piercing damage and 4 (1d8) poison damage. The target must also make a DC 17 Constitution saving throw or be poisoned for 1 minute. A poisoned creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Grasping Tail. Melee Weapon Attack: +12 to hit, reach 10 ft., 1 target. Hit: 11 (1d8 + 7) bludgeoning damage. On a hit, the target is grappled. They must make a DC 17 Dex. Save to not become fully restrained. 

Natural Agility. Allagi can use Dash or Disengage.

Hardened Scales. As a reaction to being hit by an attack, Allagi can momentarily fortify itself with a thick layer of scales, granting a +3 to their AC for the remainder of the current turn.

Quick Reflexes. When making an Opportunity Attack, Allagi can choose to use their Grasping Tail Attack in place of a Standard Attack.

Allagi can take 3 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. It regains spent legendary actions at the start of its turn.

Move. Allagi can move up to half its current movement.

Shifting Attack. Allagi can make one attack from their Shifting Attack list.

Innate Spellcasting (2 Actions). Allagi can cast one spell from their prepared spell list.