Specific trained warriors who have great knowledge over various armors and shields as well as an understanding of how they work. They have mastered techniques on how to bypass all defenses the enemy has to offer, using great precision and coordination to find weak-spots and take full advantage over it. To these Armor Slayers, armor is not a layer of unyielding protection, but rather a metal cage that traps the wearer until certain death arrives.

Understanding of Armor

At 3rd Level, you have developed a deep understanding of armors that would fascinate even seasoned blacksmiths. 

At a glance, you can instantly discern what type of armor someone is wearing, how much AC it provides, if the armor is hindering their movements (determine if they have armor feats), and if the armor is enchanted. However, you cannot tell what type of enchantment it is. To you alone, medium and heavily armored creatures must roll disadvantage on stealth checks, regardless of feats. 

You also gain Advantage on attack rolls made against creatures wearing heavy armor.

Armor Slaying Techniques

At 7th Level, you have mastered a few techniques that allow you to deal debilitating side effects to armored opponents.

You have 3 Anti-Armor Points. You may choose 2 of the following techniques below, and may take 1 additional technique at Levels 10 and 18.

Blinding Strike
Your strike aims specifically for the face. You may expend 1 Anti-Armor Point before you make an attack using a Finesse weapon against a medium or heavily-armored opponent. If your strike lands, your opponent's vision will be impaired by dripping blood. Your opponent will suffer from Disadvantage on Wisdom (Perception) and Intelligence (Investigation) Checks that involve eyesight and will suffer from Disadvantage on attack rolls until they use an Action to wipe off the blood.

Flesh Piercer
You put in immense force behind each of your strikes to pierce through the unyielding. You may expend 1 Anti-Armor Point before you make an Attack Action while using a Finesse weapon against any creature. For this Attack Action, you may ignore any resistances that may halve your weapon's damage. 

Focused Strikes
You put in immense concentration to take full advantage of any openings and weak spots available to you when attacking. You may expend 1 Anti-Armor Point before you make an Attack Action while using a Finesse weapon against a medium armored opponent. For this Attack Action, you may gain advantage on all attacks against this opponent. 

Knee Joint Cut
Your strike aims specifically for the unarmored behind-the-knee joint. You may expend 1 Anti-Armor Point before you make an attack using a Finesse weapon against ONLY a heavily-armored opponent. If your attack lands, your opponent's speed is halved and has Disadvantage on Dexterity Checks and Saving Throws for one round. 

Leg Sweep
Your next attack aims to trip your armored opponent while utilizing the weight of their armor to make them fall. You may expend 1 Anti-Armor Point so you may use your Action to attempt to trip a medium or heavily-armored opponent. You must make a contest Strength Check against your opponent's. You may gain Advantage on your Strength check if your off-hand is empty. On a successful Strength Check against your opponent's, you manage to force your opponent to lay prone. You can also choose to either move your opponent 5 feet in any direction after a successful leg sweep or you can deal a 1d4 bludgeoning damage from the force of you slamming your opponent into the ground. 

Piercing Blow
Your next strike is a very painful one, cutting extremely deep into your opponent despite their protection. You may expend 1 Anti-Armor Point before you make an attack using a Finesse weapon against a medium or heavily-armored opponent. If your attack hits, all attacks rolls against this creature gains Advantage.

Shield Removal
Your attack specifically aims to disarm the shield from your opponent, cutting over the shield and on the wrist. You may expend 1 Anti-Armor Point and attempt to remove your opponent's shield as a Bonus Action. You make one normal attack roll using a Finesse weapon, and if your attack lands, then you may remove your opponent's shield with your free off-hand. You may equip your opponents shield all within this one Bonus Action. 

Shoulder Joint Cut
Your attack specifically aims for the unarmored armpit shoulder joint. You may expend 1 Anti-Armor Point before you make an attack using a Finesse weapon against ONLY a heavily-armored opponent. If your attack lands, your opponent will suffer from Disadvantage on attack rolls, cannot make Attacks of Opportunity, and has Disadvantage on Strength Checks and Saving Throws for one round.

Anti-Armor Martial Arts

At 10th Level, you are practiced in hand-to-hand combat against armored opponents, knowing how and where to strike them to inflict the most pain.

Your unarmed strike against medium and heavily-armored opponents gain Advantage on attack rolls and deal 1d4 bludgeoning damage. You may also attack with an unarmed strike as a Bonus Action against medium and heavily-armored opponents.

Anti-Armor Action Surge

At 15th Level, you have honed your skills and techniques so that you can take down the most armored opponents without fail. 

On your turn, when fighting against a heavily armored opponent and wielding a Finesse weapon, you may take one additional action on top of your regular action, Action Surge action, and possible bonus action. 

You may use this feature once per Long Rest. 

Armor Breaker

At 18th Level, you have pushed beyond what is normally possible for a warrior and found techniques to make enemy defenses weaken mid-battle. 

When attacking a medium armored, heavily armored, or a creature with at least 15 AC (without added Dexterity Modifier), you may have one attack reduce their armor's AC permanently by 2 or temporarily reduce their Constitution Modifier's AC by 1 for one minute. You can continue to apply this effect on until your opponent's armor's and Constitution Modifier's AC has been depleted. 

You may only apply this effect once per round, and is stackable on a single enemy. You may use this feature 3 times between Long Rests.