Blue Dragonborn Assassin

Assassinate. During its first turn, the dragonborn has advantage on attack rolls against any creature that hasn't taken a turn. Any hit the dragonborn scores against a surprised creature is a critical hit.

Evasion. If the dragonborn is subjected to an effect that allows it to make a Dexterity saving throw to take only half damage, the dragonborn instead takes no damage if it succeeds on the saving throw, and only half damage if it fails.

Innate Spellcasting. The dragonborn’s innate spellcasting ability is Intelligence (spell save DC 12, +4 to hit with spell attacks). It can innately cast the following spells, requiring no material components:

At will: lightning lure, shocking grasp

2/day each: lightning arrow, call lightning

Sneak Attack. Once per turn, the dragonborn deals an extra 14 (4d6) damage when it hits a target with a weapon attack and has advantage on the attack roll, or when the target is within 5 feet of an ally of the dragonborn that isn't incapacitated and the dragonborn doesn't have disadvantage on the attack roll.

Multiattack. The dragonborn makes two melee attacks.

Storm Dagger. Melee or Ranged Weapon Attack: +6 to hit, reach 5 ft. or range 20/60 ft., one target. Hit: 7 (1d4 + 3) piercing damage plus 19 (3d12) lightning damage. Hit or Miss: The dagger magically returns to the dragonborn’s hand immediately after a ranged attack.

Hand Crossbow. Ranged Weapon Attack: +6 to hit, range 30/120 ft., one target. Hit: 6 (1d6 + 3) piercing damage, and the target must succeed on a DC 12 Constitution saving throw or be poisoned for 1 hour. If the saving throw fails by 5 or more, the target is also unconscious while poisoned in this way. The target wakes up if it takes damage or if another creature takes an action to shake it awake.

Lightning Breath (Recharges after a Short or Long Rest). The dragonborn exhales lightning in a 30-foot line that is 5 feet wide. Each creature in that line must make a DC 13 Dexterity saving throw, taking 9 (3d6) lightning damage on a failed save, or half as much damage on a successful one.