Byakko

Keen Smell. Byakko has advantage on Wisdom (Perception) checks that rely on smell.

Pounce. If Byakko 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 13 Strength saving throw or be knocked prone. If the target is prone, Byakko can make one bite attack against it as a bonus action.

Feline Agility. When Byakko move on its turn in combat, it can double its speed until the end of the turn. Once it used this trait, it can't use it again until it move 0 feet on one of your turns.

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

Multiattack. Byakko can use its Frightful Presence. It then makes three attacks: one with its bite and two with its claws.

Bite. Melee Weapon Attack: +12 to hit, reach 5 ft., one target. Hit: 21 (2d8 + 5) piercing damage.

Claw. Melee Weapon Attack: +12 to hit, reach 5 ft., one target. Hit: 17 (2d6 + 5) slashing damage.

Frightful Presence. Each creature of the dragon's choice that is within 120 feet of the dragon and aware of it must succeed on a DC 16 Wisdom saving throw or become Frightened 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. If a creature's saving throw is successful or the effect ends for it, the creature is immune to the dragon's Frightful Presence for the next 24 hours.

Energy Ray (Recharge 5-6): Byakko lets out a lightning beam from its mouth in a 90-foot line that is 5 ft. wide. Each creature in that line must make a DC 19 Dexterity saving throw, taking 66 (12d10) lightning damage on a failed save, or half as much damage on a successful one.

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. Spent legendary Actions are regained at the start of each turn.

Detect: Byakko makes a Wisdom (Perception) check.

Claw Attack: Byakko makes a tail Attack.

Gust Attack (Costs 2 Actions): Byakko beats conjures a strong whirlwind around it. Each creature within 10 ft. of Byakko must succeed on a DC 19 Dexterity saving throw or take 13 (2d6 + 6) bludgeoning damage and be knocked prone.