Those who follow the Way of the Mantis liken themselves to that of the powerful Preying Mantis. Studying the hunting techniques of the Mantis. Relying on cunning, strength, and attacks of opportunity. Monks who train to emulate the movements of the Mantis know full well how patient a successful hunter must be, and that when you strike it pays to be accurate more than anything.

Mantis Style: At 3rd level, your training teaches you a new fighting stance, Mantis Style. With your feet planted firmly in the ground making you hard to get off balance giving you advantage on Saving Throws against being knocked back, grappled, or knocked prone.  When a creature melee attack misses you may spend 2 ki point to counterattack as a reaction. Can only use this feature once per turn and you cannot use it on missed attacks of opportunity.
When you miss an unarmed attack you may spend 2 ki to reroll your hit dice.
In addition your unarmed strikes can cause piercing damage instead of bludgeoning, and have an increased range of 5ft.

Crippling Blow: Also at 6rd level, your strikes are accurate and precise able to find and puncture the weakest points of your target's defenses. When you hit another creature with an unarmed strike you can spend 1 ki point to attempt to blind, trip, deafen, or slow the enemy. Choose 1 condition to effect the creature. You may spend 2 extra ki point and choose a second condition.  

Paralyzing Palm Strike: At 11th level your commitment to your training has rewarding you with supremely accurate strikes and knowledge of the pressure points of creatures. When you hit another creature with an unarmed attack you may spend 4 ki points to paralyze that creature.

Patient Hunter: At 17th level studying the Mantis has taught you that those who wait are rewarded. You may spend 3 ki points to guarantee a critical strike against a target that has attacked you or a creature you can see on its last turn. This attack cannot miss, the creature may make a DEX saving throw to take half damage.The attack does 1 extra attack dice of piercing damage.
You can use this ability twice per long rest, can replenish 1 use in a short rest.
When you hit a critical on an attack roll you regain 4 ki points.

Mantis Style

At 3rd level, your training teaches you a new fighting stance, Mantis Style. With your feet planted firmly in the ground making you hard to get off balance giving you advantage on Saving Throws against being knocked back, grappled, or knocked prone.  When a creature melee attack misses you may spend 1 ki point to counterattack as a reaction. Can only use this feature once per turn and you cannot use it on missed attacks of opportunity.
When you miss an unarmed attack you may spend 1 ki to reroll your hit dice.
In addition your unarmed strikes can cause piercing damage instead of bludgeoning, and have an increased range of 5ft.

Crippling Blow

Also at 6rd level, your strikes are accurate and precise able to find and puncture the weakest points of your target's defenses. When you hit another creature with an unarmed strike you can spend 1 ki point to attempt to blind, trip, deafen, or slow the enemy. Choose 1 condition to effect the creature. You may spend 2 extra ki point and choose a second condition.

Paralyzing Palm Strike

At 11th level your commitment to your training has rewarding you with supremely accurate strikes and knowledge of the pressure points of creatures. When you hit another creature with an unarmed attack you may spend 4 ki points to paralyze that creature.

Patient Hunter

At 17th level studying the Mantis has taught you that those who wait are rewarded. You may spend 4 ki points to guarantee a critical strike against a target that has attacked you or a creature you can see on its last turn. This attack cannot miss, the creature may make a DEX saving throw to take half damage.The attack does 1 extra attack dice of piercing damage.
You can use this ability twice per long rest, can replenish 1 use in a short rest.
When you hit a critical on an attack roll you regain 4 ki points.