Mistweaver

You have spent your life hiding in the mists. Swirling clouds of fog are your friend, a protective covering that hides you from prying eyes. You become well-versed in navigating without relying on your sight and striking foes that cannot see, while remaining hidden from view. 

Mist Walker

Beginning at 3rd level, you can summon mists at any time. You gain the ability to cast fog cloud, with the target being self. Once you have used this feature a number of times equal to your Wisdom modifier, you must complete a long rest before you can use it again.

One with Shadows

Starting at 3rd level, you are comfortable when surrounded by fog. When you are surrounded by your mist, you gain advantage on Dexterity checks and can see through it as if the area wasn't heavily obscured. In addition, moving through nonmagical difficult terrain costs no extra movement if you are under the cover of mist.

Mistsense

Starting at 9th level, you have learned the nuances of the mist. Once in the mist, you gain mistsense. Mistsense activates once you enter the mist, and while within the mist, you can sense any creature whose position resides within the mist, regardless of illusions and if you can see them or not.

Toxifying Mist

Beginning at 13th level, you can infuse the mist you create with ancient poisonous arts and use that to your advantage. Whenever you cast the Fog Cloud spell, you can cause it to become toxic. Until the spell ends or the mist is dissipated, you can use a bonus action to cause the poisonous reagents within the mist to disperse, forcing every hostile creature within the mist and within 10ft of it to make a DC 15 Constitution saving throw. On a fail, the creature takes 1d6 poison damage and is poisoned until the end of your next turn. If you use this bonus action while a creature is already poisoned, they have disadvantage on the save and take an extra 1d6 poison damage on a fail. On a success, they take half damage and suffer no additional effects. 

Mist Keeper

At 17th level, you learn to manipulate your mist's toxic nature to the fullest extent. While a hostile creature resides within your mist or within 30ft of it, they are poisoned regardless of saving throws, resistances, and immunities. Additionally, any poison damage you do also bypasses any resistances and immunities.