Iron Finial (5e Equipment)

Rod, very rare (requires attunement by a spellcaster)

A huge, simple metal rod, covered in small markings. It is slightly warm to the touch.

This rod has a maximum of 50 charges. When something within 100 feet of you takes lightning damage, you can use your reaction to reduce the damage dealt by 4d10(minimum 0), the rod gaining half as many charges that it reduced the damage by. When you cast a spell that deals lightning damage, you can spend any amount of charges to deal extra damage equal to the charges spent.

This weapon loses all charges at dawn, and if you ever try to reduce more damage while it is currently at 50 charges, the rod explodes, becoming a nonmagical assortment of metal scrap.