Lightning Shield (5e Equipment)
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Armor (shield), very rare (requires attunement)
While you are wielding this metal shield, you have immunity to lightning damage.
You can use a bonus action to speak this magic shield's command word, causing lightning to crackle across its surface. The lightning sheds bright light in a 15‑foot radius and dim light for an additional 15 feet. While the shield is electrified, any creature that hits you with a melee attack while within 5 feet of you takes 2d4 points of lightning damage, or 2d8 points of lightning damage if it attacked you with a weapon made of metal.
You can use this shield to make a shove attempt on your turn as a bonus action, shoving a creature with a shield. If the shield is electrified and you win the contest, the creature takes 2d4 lightning damage in addition to the normal effects of a successful shove, or 2d8 lightning damage if it is wearing armor made of metal.
The shield remains electrified until you use a bonus action to speak the command word again or until you drop or stow away the shield.