The Bastion

Being no stranger to the battlefield, you have seen countless allies fall all whilst your foes get the best of you. Most of the time, the only thing that was between you and what could potentially be your gruesome fate was the very shield you carry. After undergoing training, you've formed this style of fighting into something new entirely, becoming an immovable bulwark of steel, shielding allies from any potential harm whilst setting them up for the finishing strike.

Improved Protector

Starting when you choose this archetype at 3rd level, you learn to utilize your shield more effectively during combat. You gain the following benefits whilst wielding a shield:

• At the end of your turn, you can choose one ally within 5 feet of you. That ally gains a +2 AC against Weapon Attacks until the start of your next turn. If they move out of your range on their turn, this benefit ends. Starting at 10th level, this bonus to AC becomes +3 and can be applied against Spell Attacks.
• Whilst standing behind you, a friendly creature of your choice can gain ½ cover against Ranged Weapon Attacks. Starting at 10th Level, this becomes ¾ cover and can be applied to Ranged Spell Attacks.

Crippling Strike

At 7th level, you learn a potent maneuver that can set up the attacks of your allies. Whenever you take the attack action on your turn, you can use one of your attacks to strike a creature within 5ft of you with your shield. Make a melee weapon attack, adding your strength score + proficiency modifier to the roll. On hit, the attack deals 1d6 + your strength modifier in bludgeoning damage and the creature must succeed a Constitution Saving throw, or become subjected to one of the following effects. On a critical hit, this effect immediately goes off without a saving throw. At this level, the shield attack can only critically hit on a roll of a 20. Making this attack with a magical shield makes Crippling Strike magical, but does not apply any bonuses to hit.

Crippling Strike DC = 8 + your proficiency bonus + your strength modifier

• The target gains disadvantage on all weapon attacks it makes until the start of your next turn.
• The target cannot move further than 10ft on its turn. If it takes the action to dash, it can only do so for a further 10ft. This effect lasts until the start of your next turn.
• The next attack against the creature has advantage.

Shield Expert

At 10th level, your mastery with the shield starts to become more and more obvious. Wielding a shield now gives you a +3 bonus to your AC.

Unwavering Endurance

Starting at 15th level, you can push your endurance even further during combat. If you are reduced to 0 hit points and still have a use of Second Wind, you can use your reaction to instead be reduced to 1 hit point and immediately use your Second Wind feature. Once you use this feature, you cannot do so again after you finish a long rest.

Aegis

At 18th level, your skill with the equipment in your hands makes you exude a presence on the battlefield that is enough to turn the tide of even the most dire situation. You gain the following benefits:

• Whenever you use your action surge, two allies of your choice within 10 ft. of you can immediately make an opportunity attack against one creature of your choice. Both allies must strike the same creature.
• Whenever you use your second wind feature, one ally of your choice within 10 ft. of you gains a number of hit points equal to your Fighter Level.
• If your shield adds a magical bonus to your AC, you also add said bonus to the attack and damage rolls you make with Crippling Strike. Additionally, Crippling Strike now critically hits on a roll of a 19-20.