Elemental energy wreathes your body for the duration, shedding bright light in a 10-foot radius and dim light for an additional 10 feet. You can end the spell early by using an action to dismiss it. When the shield first appears, you decide whether it is made of acid, cold, fire, lightning, or thunder energy.

The shield grants you resistance to the damage of your chosen elemental type.

In addition, when a creature within 5 feet of you hits you with a melee attack, the shield erupts with energy. The attacker takes 2d8 damage of the chosen type.