Sentinel

Valiant heart, unwavering resolve.

Living Wall

You have honed your body to act as a living wall, standing to fight forever.
    When you are targeted with an attack and are using a shield, you can use your reaction to grant yourself temporary hit points equal to your Fighter level + your proficiency bonus.
    This feature can be used a number of times equal to your proficiency bonus per long rest.

Shield Master

While you wield a shield in one hand and are unarmed in the other, you gain the benefits of the Shield Master feat (this does not stack with the feat), as well as the following benefits:
    You are proficient in attacking with shields. Your shield has a d6 damage die.
    When you make an attack with your shield, any unarmed attack made after gains an extra d4 force damage.

Sentinel Shield

You gain the ability to magically imbue your shield with energy. On your turn, when you are wielding a shield in one hand and are unarmed in the other, you may activate this ability for 1 minute as a bonus action. For the duration, you gain the following benefits:
    Code of the Protector. When an enemy within melee range makes an attack against your ally, you may use your reaction to impose disadvantage on the attack and attack the enemy once with your shield as part of the same reaction.
    Code of the Commander. Whenever you make an unarmed strike against an enemy, any allies within 15 ft can make an attack on that same enemy, using their reaction, if they are in range.
    Code of the Aggressor. When you make an attack with your unarmed strike as part of the attack action, you gain one extra attack in that action which can only be an unarmed strike.
    This ability ends early if you hold a weapon that isn't a shield or dismiss it as an action. It can be used once per long rest at 10th level and once per short rest at 15th level.

Ward of Dawn

The energy in your shield when you use Sentinel Shield is geared towards defense. While Sentinel Shield is active, you can use one of your attacks from the attack action to guard with your shield. When you do so, you gain the following benefits.
    Two 5 foot wide, 10 feet tall walls of force sweep out on either side of your shield. Any allies behind this wall, excluding you, can use it as total cover. Any attacks made by allies originating from one side of the wall passing through to the other side gain an extra d8 force damage.
    You gain 4 AC in addition to your shield bonus.

Walls Don't Care

Your body is built to withstand limitless amounts of pressure and retaliate with unmatched aggression. You gain the following benefits.
    In the Trenches. Any time an enemy dies while Sentinel Shield is active, whether that kill is made by you or allies, roll a d12. On a roll of a 12, you regain your use of Sentinel Shield.
    Rallying Force. Your unarmed strikes deal an additional d10 force damage, and whenever you get a kill with an unarmed strike, you and any allies within 30 feet gain temporary hit points equal to d6+your Constitution modifier.
    Turn the Tide. Whenever an ally is brought beneath half of their maximum hit points and the damage that did so came from a creature within 20 feet, you can use your reaction to move up to 20 feet towards the creature and make 2 attacks as part of the same reaction. This range increases to 30 feet when Sentinel Shield is active.