Armor of Despair

You unleash a wave of negative energy, infusing your armor with despair and sorrow. For the duration of the spell, you gain the following benefits:

Your Armor Class increases by 4.
You have resistance to necrotic damage.
Whenever a creature within 30 feet of you makes an attack roll or ability check, you can use your reaction to force it to make a Wisdom saving throw. On a failed save, the creature is overcome with despair, and its attack or ability check automatically fails.
In addition, whenever a creature within 30 feet of you takes damage, you can use your reaction to force it to make a Wisdom saving throw. On a failed save, the creature is filled with overwhelming despair, and it takes an additional 3d6 necrotic damage.