Defender

Defenders are warriors who gain great defensive abilities.  They possess a higher armor class, and gain damage reduction while using a shield.  Defenders can also gain bonuses from a defensive stance ability, if they stay rooted in one spot.  Their shield becomes a weapon, that can also increase their armor class, and helps them to provoke enemies into focusing on them.  They also are great at protecting their allies from enemy attacks, while near the defender.

Shield Slam

When choosing this archetype, at 3rd level, gain the ability to slam your shield into the enemy for 1d4 damage, gaining +2 AC until the start of your next turn.

Additionally, when using shield slam, you may use your bonus action to provoke the enemy into attacking you.  The target must make a [8 + proficiency + CHA modifier] charisma saving throw, or be forced to attack the Defender on their next turn.

Defensive Stance

Starting at 7th level, gain the ability to enter into a defensive stance for 1 minute.  Usable once at level 7, twice at level 12, and three times at level 18.  Recharges once per short rest, fully per long rest.  While in defensive stance, your movement speed is reduced to zero. 

While in the stance gain the following:

• At the beginning of each round gain temporary hit points equivalent to your level plus constitution modifier, up to a maximum of your level plus constitution modifier.
• AC increased by 2.
• Enemy attacks to allies within 5 feet are at disadvantage.
• Gain resistance to all ranged projectiles.

After defensive stance ends, any remaining temporary hit points are lost.

Additional Fighting Style

At 10th level, you adopt an additionally style of fighting.  Choose one of the following options.  You can't take a Fighting Style option more than once, even if you later get to choose again.

Archery

You gain a +2 bonus to attack rolls you make with ranged weapons.

Defense

While you are wearing armor, you gain a +1 bonus to AC.

Dueling

When you are wielding a melee weapon in one hand and no other weapons, you gain a +2 bonus to damage rolls with that weapon.

Great Weapon Fighting

When you roll a 1 or 2 on a damage die for an attack you make a melee weapon that you are wielding with two hands, you can reroll the die and must use the new roll, even if the new roll is a 1 or a 2.  The weapon must have the two-handed or versatile property for you to gain this benefit.

Protection

When a creature you can see attacks a target other than you that is within 5 feet of you, you can use your reaction to impose disadvantage on the attack roll.  You must be wielding a shield.

Two-Weapon Fighting

When you engage in two-weapon fighting, you can add your ability modifier to the damage of the second attack.

Concussive Blow

Forcibly slam your shield and weapon into the enemy, in an attempt to disorient them from battle. The target must make a constitution saving throw greater than 8 plus your strength modifier or be stunned until their next turn.

Unstoppable Force

Starting at 18th level your Defense Stance ability no longer ends after 1 minute, and goes until you end it.   Additionally, you may now move half of your movement speed while in defensive stance.

In addition, while in defensive stance, you gain the ability to Fortify, raising your shield to protect yourself and allies from 

• Resistance to all bludgeoning, slashing, and piercing damage.
• Your shield now blocks you from all ranged projectiles, causing them to deal no damage to you.
• Allies within 5 feet of you, but not in front of you, also gain resistance to all ranged projectiles.