Child of Tarin

Legendary Resistance: The dragon has legendary resistance. Once per day when it would fail a saving throw it can instead choose to succeed. 

Mental Resistance: The dragon has advantage on intelligence and Charisma checks and saving throws. 

Spellcasting:  The dragon may cast Magic Missile at 3rd level, 3 times per long rest.

Glide: The dragon cannot fly, but takes no damage from falling while conscious and unrestrained. 

Multiattack. The dragon makes two attacks. One with its claws, and one with its bite. 

Claw. Melee Weapon Attack+10 to hit, reach 5 ft., one target. Hit: 2d6 + 6 slashing damage.

Bite. Melee Weapon Attack+10 to hit, reach 5 ft., one target. Hit: 3d8 + 8 force damage. Targets of size medium or smaller which are hit with a bite must succeed on a DC 15 Strength saving throw or be swallowed. Only one medium sized creature, or two creatures smaller than medium size may be swallowed at a time. Swallowed creatures take 2d6 poison damage at the start of their turn and may use their action to repeat the strength saving throw to escape from within the dragon. 

Enervating Breath [rollable](Recharge 5-6); The dragon exhales a smog of pitch black in a 60-foot cone. Each creature in that area must make a DC 17 Dexterity saving throw, taking 6d10 force damage on a failed save, or half as much damage on a successful one. Creatures which fail their save have their speed reduced by half for 1 minute. They attempt a DC20 constitution saving throw at the end of each of their turns to end this effect early. 

Each Child of Tarin has 2 legendary actions per round, which can be used at the end of another creatures turn.

Claw (1 action): The dragon takes one melee attack with its claw against a creature in range

Inhale (2 actions): The dragon attempts to regain its enervating breath attack (roll a d6, the dragon regains its breath on a 5-6).