The Venom Fist (Edited)

You might have been raised in a Temple dedicated to the arts of assassination or perhaps you are a lizard folk with distant relations to the Yuan-ti. Whether it was alchemical experimentation or thru a particular training regiment, your body has developed a mutation where your hands are not only deadly weapons: but poisonous too.

(Minor edits took place after some considerations were made after some further testing. )

Venomous Strike

When Choosing this class at 3rd level your fists gain a venomous edge to them. As an action you can spend one ki point for a poisonous venom to coat your hands, arms or feet.This coating lasts for one minute. When you strike a creature with an unarmed strike, they have to make a Constitution Saving throw(DC = 8 + Proficiency + Constitution Modifier). Should they fail they are poisoned(Disadvantage on attack rolls and ability checks). They can make another Constitution saving throws at the end of subsequent turns to end the effect.

You can end the Venomous Strike feature as a bonus action. You are immune to your own venom and You cannot apply your Venomous Strikes to a weapon you are holding but it can be applied to natural weapons such as claws and teeth.

After you have poisoned someone with your venomous strikes, they cannot be poisoned again until a number of rounds equal to the creature's Constitutien modifier has been elapsed(minimum of 1). You can afflict a different condition at later levels with your strikes and they follow the same limitation.

You also gain Proficiency in alchemist's tools or a poisoner’s kit.

Venomous Roil

At 6th Level your internal venom has become more potent and your body is used to sheltering dangerous toxins. When you hit with your Venomous strikes, you can add your Constitution Modifier on your Damage rolls as poison damage.

Additionally your poison has learned to act like a virus, rapidly adapting to the immune system of a creature. When you hit with a Venomous strike you ignore Resistance to Poison Damage and Immunity to the Poisoned condition and if a creature fails the saving throw for your venomous strike (on both the initial and subsequent savings at the end of each turn) your target takes additional poison damage equal to 2 + Constitution Modifier.

Viper’s Kiss

At 11th Level your poison has grown in lethality as well as variety. When you Hit with your Venomous Strike you can choose to afflict a different Condition: Blinded or Deafened. You must spend an additional ki point to afflict a different Condition.(When you first activate your Venomous strikes you always start with afflicting the Poisoned condition). Also if any creature is unable to suffer from these conditions, such as having no eyes for the Blinded condition or is physically unable to be deafened, then treat them with regular immunity as the creature will be unaffected. Elsewise you ignore immunity to those Conditions.

Additionally Your Venomous Strikes Ignore Immunity to the Poisoned Condition and Immunity to Poison Damage.

Insidious Body

At 17th Level you have Mastered the writhing venom with you. Whenever a creature hits you with Slashing, Piercing, or any other damage type that cuts the skin, they must make a Dexterity saving throw or Take Double your Con modifier in Poison Damage.

Additionally you can select 2 more Conditions for your strikes to apply on hit: Paralyzed or Incapacitated. You no longer need to pay ki to change the Condition.