Ravager

Soldiers of repute and renown for their intense fighting style. They fight with shields and flails, laying out relentless litany of strikes while maintaining an impenetrable guard. 
Lesser warriors break like water on rock when they bring arms to bear against a Ravager, and weaker beings buckle and snap under the overwhelming pressure they dole out.

Flail Master

Beginning when you take this archetype at 3rd level, you gain a +2 to attack and damage rolls you make with flails. This bonus increases to +3 at 10th level, and +4 at 18th level.

Shield Expertise

• You can make an attack action with a shield as a bonus action dealing 1d6 points of bludgeoning damage.
• As long as you are aware of an attack and not otherwise incapacitated, you can add your shields AC bonus to your Dexterity saves against damaging spell or attack effects, such as breath weapons.
• When faced with a Dexterity save for half damage while wielding a shield, if you succeed, you instead suffer no damage.

Vicious Rebuttal

Upon receiving a melee attack from an enemy within your reach, hit or miss, you may use your reaction to immediately  make a melee weapon attack with your flail or shield bash against them.

Staggering Guard

When a creature misses you with a melee attack, you may use your reaction to make a shield bash attack against them. On a hit, the target takes no damage, but is stunned until the end of your next turn.

Overwhelming Strikes

When you take the attack action in a round in which you have not moved, you may make an additional attack as part of the action. You may not move for the rest of the round if you attacked in this way.

Unshakable Shield

As a bonus action, you may enter a defensive stance until the beginning of your next turn. While in this stance, your movement speed is reduced to zero, and you gain a bonus to your armor class equal to your proficiency bonus.