Ashen Assassin

Innate Spellcasting. The ashen abomination's innate spellcasting ability is Intelligence (spell save DC 15, +5). The ashen abomination can innately cast the following spells, requiring no material components.

At Will: Fire Bolt, Misty Step

1/day: Fog Cloud

Magic Weapons. The ashen abominations weapon attacks are magical.

Water Susceptibility. For every 5 feet the ashen abomination moves in 1 foot or more of water, it takes 5 (1d10) cold damage.

Ashen Shroud. The creature is surrounded by a shroud of ash that obscures vision. The aura dissipates when blown by strong wind or after the creature is reduced to half their maximum hp. Whilst surrounded by this ash, all attacks on the creature that rely on sight have disadvantage.

Sneak Attack. Once per turn, the assassin 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 assassin that isn't incapacitated and the assassin doesn't have disadvantage on the attack roll.

Multiattack. The elemental makes two attacks, one with with their Ash Blade and one with their Flame Whip.

Ash Blade. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 7 (1d6 + 4) piercing damage. The target then takes 7 (2d6) fire damage as the blade that pierces the target also stings with heat.

Flame Whip. Melee Weapon Attack: +7 to hit, reach 10 ft, one target. Hit: 6 (1d4 + 4) slashing damage plus 7 (2d6) fire damage.