The guardian is at the forefront of battle, placing themselves between their foes and their allies. A guardian takes the brunt of damage, acting as a walking tank and placing themselves in harms's way to defend their allies.

Defensive stance

At 3th  level, as an action you can take an all out defensive stance when wielding a shield. While you're in this stance you have resistance to all damage except psychic and necrotic, and add your proficiency bonus to your AC. You movement speed is halved when you are in a defensive stance. The stance lasts until your next turn.

At 7th level you may enter a Defensive Stance as a bonus action instead of an action.

At 15th level you may hold Defensive Stace for 1 minute.

Protect Ally

At 7 level, as a reaction you may protect an ally that is within 5 feet of you. That ally gains advantage on saving throws until end of turn and gain AC equal to your proficiency bonus. You may use this ability a number of times per day equal to 1 + your  Con or Dex bonus (whichever is higher)

Spell sheild

Starting at 10th level, when you enter Defensive Stance create a 15 foot cube safe haven behind you. Allies within this cube add your shield's AC bonus to all saving throws they make against spells or other harmful attacks. If you or an ally withing this cube are subjected to make a saving roll to take only half damage, they take no damage on a successful saving throw.

 

Draw Ire

Beginning at 15th level, if an enemy you can see or hear makes a single attack against an ally, as a reaction you may force that enemy to attack you instead. If the enemy can see or hear you is must make a Wisdom saving throw against your Intimidation (Charisma) check, and if it fails you become the target of that same attack instead. You can use this ability a number of times equal to 1 + your Charisma modifier per short or long rest.

Adamantine Protector

Beginning at 18th level,  you can no longer be critically hit, any attempt to knock you prone has disadvantage, the distance you can be shoved is halved, and you add your profeciency bonus to all saving throws.