One of the insectoid styles of monk disciplines, the way of The Scorpion is a deadly technique that harnesses Ki for lethal poison attacks and powerful grapples.

Stinging Strike

At 3rd level you have learned to channel your Ki into a powerful strike that emulates a scorpion's infamous stinger.

When you take the Attack action on your turn, you can forgo one of your attacks and instead perform this powerful strike. Make an unarmed strike against a target within 5 feet. On a hit, the target takes 2 martial arts dice of piercing damage and must succeed on a Constitution saving throw, taking 2 martial arts dice of poison damage or half as much on a successful one.

You can perform this strike a number of times equal to your proficiency bonus, and regain all expended uses on a long rest. If you have no uses remaining, you may spend a number of Ki points equal to your proficiency bonus to use this feature.

The damage dealt by this attack increases as you gain levels in this class: 3 dice for both damage types at 6th level, 4 dice for both damage types at 11th level, and 5 dice for both damage types at 17th level.

Pincer Grip

Also at 3rd level, you learned to effectively grapple your opponents to ensure your Stinging Strike hits. 

As a bonus action, you may spend one Ki point to attempt this grapple. When you do, make an Unarmed Strike. On a hit, the target takes damage as normal and becomes Grappled if it is Large or smaller. While a creature is grappled in this way, you have advantage on the attack roll for your Stinging Strike. A creature grappled in this way can attempt an Athletics (Strength) check against your Ki save DC at the end of its turns, breaking free on a success.

Stunning Stinger

By 6th level, you have learned to combine the poison of your Stinging Strike with your monk expertise of Ki manipulation.

When you perform a Stinging Strike, you may spend 1 Ki point to also induce the effects of your Stunning Strike monk feature when you hit. The saving throw for the Stunned effect is the same as the one rolled against the poison.

Poison Spray

Also by 6th level, you have learned to attack with your poison from range, as well as use it to induce extra effects.

When you take the Attack action on your turn, you may forgo one of your attacks and expend one usage of Stinging Strike in order to perform this ranged attack. Choose one creature within 30 feet of you. That creature must succeed on a Dexterity saving throw or take 3 martial arts dice of poison damage. If they fail the saving throw by 5 or more, they also become blinded until the end of your next turn.

The damage dealt by this feature increases to 4 dice at 11th level, and 5 dice at 17th level.

Superior Sting

By 11th level, your Ki has become so powerful that your poison attacks can penetrate even those usually resistant to such effects.

Poison damage dealt by your Monk features ignores Resistance to Poisons and Poison damage, as well as treating Immunity as Resistance.

Additionally, you can now grapple Huge creatures with your Pincer Grip.

Varied Toxin

By 17th level, you have learned to alter the type of venom you produce to change the effect of it.

When you hit with a Stinging Strike and the target fails its Constitution saving throw against the poison, you may spend 1 Ki point to also induce on of the following conditions: Blinded, Deafened, or Paralysed.

Additionally, if you target a creature with Immunity to poison with a Stinging Strike, that creature must succeed on a Constitution saving throw or have its Immunity ignored for the triggering attack.