Archmage's Ward

Utilizing the elemental forces that make up the planes of existence you place a powerful arcane ward on your self, choose one element, you gain immunity to that element and attacks against you trigger a backlash from the ward depending on the element.

Lightning: physical attacks against force the target to make a constitution saving throw against your spell save DC, on a failure they become paralyzed for 1 minute and take 1d8 lightning damage and may repeat the saving throw at the end of each of their turns, on a success the attacker does not become paralyzed.

Thunder: Melee attacks against you trigger a shock wave against all units withing 5 feet of you causing them to take 1d8 thunder damage and forcing them to make a strength saving throw against your spell save DC or be knocked back and prone 15 feet away from you.

Fire: Melee attacks against against cause a tendril of fire to lash out at the attacker forcing them to make a dexterity saving throw against your spell save DC taking 4d8 fire damage on a failure and half as much on a success.

Cold: Projectile attacks against you fire ice shards at the attacker, dealing 2d6 cold damage to the target.

Acid: Melee weapon weapon attacks against cause the weapons to corrode if they are non magical and non adamantite, melee attackers also suffer 3d4 acid damage.

Force: You are immune to magic missile, and ranged attacks against you have disadvantage, and non magical arrows shatter before reaching you.

Poison: Melee attackers suffer 1d8 poison damage and must succeed on a constitution saving throw against your spell save DC or become poisoned for an hour.

Depending on your alignment you may choose on of the following

Good:

Radiant: Upon being struck enemies take 1d8 radiant damage, and up to half the damage you take can be used to heal all allies around you for the same amount.

Neutral:

Psychic: Upon being struck enemies take 1d8 psychic damage, attackers must make a wisdom saving throw against your spell save DC or become frightened of you and see you as the creature they fear the most.

Evil:

Necrotic: Upon being being struck by a melee attack enemies take 1d8 necrotic damage, attackers must make a constitution saving throw against your spell save DC or be afflicted by a rotting ailment for 1 minute causing them to take 1d6 necrotic at the start of each of their turns, if they die while under this effect they rise as a zombie under the casters control for the next 1 hour.