|First appearance:||Cronus Vanquished|
Thanatos, the God of Death, serves whoever wears Hades's Helmet of Darkness, thus he obeys the ruler of the The Underworld. He appears as a mild-mannered and soft-spoken middle aged man, but his true form is a skeletal winged creature who is able to appear from shadows and disappate into the air. When Cronus seizes control the Underworld, he summons Thanatos to kill the heroes. The God of Death successfully kidnaps Archie, forcing the heroes to enter the Underworld to rescue their friend as well as Hades and Persephone. He is later confronted by the heroes when Sisyphus escapes from the Underworld and agrees to be chained temporarily until Theresa is rescued so that she cannot die until Sisyphus is recaptured.