Sentinel

Defensive Fighters

Based around extra reactions for defensive/disruptive maneuvers.

Defensive Fighting

At 3rd level, you learn the Defensive Stance feature which grants you additional reactions for specific defensive maneuvers.

As a bonus action, you can sacrifice 15 feet of your movement to enter a Defensive Stance.

Defensive Stance:

You gain 1 free reaction until the start of your next turn. This reaction must be used for a Sentinel maneuver.

You gain +1 AC until the start of your next turn.

At 7th, 15th, and 18th level, you gain an additional free reaction.

Sentinel Maneuvers

 At 3rd level, you learn the following Sentinel Maneuvers.

Crushing Counterstrike

Whenever you, or an ally within your reach is targeted by a melee attack, you can use a reaction to make an opportunity attack against the attacker.

If the attack hits, the target takes additional damage equal to your strength modifier, and must succeed a Strength Saving Throw or be pushed back 5 feet and knocked prone.

If the attacker fails the save, the attack automatically misses.

Save DC = 8 + Proficiency bonus + Strength Modifier

Defend Ally

When an ally within your reach is targeted by a melee attack, you can use a reaction to force the attack to target you instead.

If the attack misses, you can make a free opportunity attack against the attacker

Guard

Designate 1 ally within 5 feet. That ally gains the AC bonus of your shield until the start of your next turn.

You can only guard 1 ally at a time.

Take the Blow

When an ally within 5 feet would take damage from an attack, or a spell requiring a Dexterity Saving Throw, you can use your reaction to take the damage yourself.

In addition, the targeted ally can move up to 10 feet without provoking opportunity attacks.

Defiant Durability

At 7th level, whenever you make a saving throw, roll 1d6 and add the die to your saving throw total. If applying this bonus to a death saving throw increases the total to 20 or higher, you gain the benefits of rolling a 20 on the d20.

Shielded Evasion

At 10th level, if you have a shield equipped,  when you are subjected to an effect that allows you to make a Dexterity saving throw to take only half damage, you instead take no damage if you succeed on the saving throw, but full damage if you fail.

Shield Adept

at 15th level, you gain an additional +1 AC from shields.

In addition, if you have taken the attack action, you can spend a bonus action to make an additional melee attack with your shield. It deals 1d6 + STR modifier bludgeoning damage, and you are proficient with it.

Master of Defense

at 18th level, you may make opportunity attacks even if you have already spent your reaction this round.