Armor of the Nameless Son (5e Equipment)
From D&D Wiki
Armor (half plate), legendary (requires attunement)
This magic half plate armor grants its wearer advantage on saving throws against the breath weapons of dragons, and resistance to both fire damage and lightning damage.
The armor of a rogue God that betrayed his brethren to save the very creatures he once hunted. He was banished from the land of Gods and his name erased from the annuls of history entirely; statues made in his image torn down and deific status revoked. He took to the skies and harnessed the power of thunder and sunlight in the form of lightning and formed a pact with a Storm Oni. Together they silently watch over his few remaining adherents bestowing upon them symbols of the sun for their good deeds towards others and occasionally granting them with the knowledge to harness the power of the sun & storm.