Frozen Stygia is ruled by Levistus, an archdevil known for offering bargains to those who face an inescapable doom.
Ability Score Increase. Your Constitution score increases by 1.
Legacy of Stygia. You know the Ray of Frost cantrip. Once you reach 3rd level, you can cast the Armor of Agathys spell once as a 2nd-level spell. Once you reach 5th level, you can also cast the Darkness spell once. You must finish a long rest to cast these spells again with this trait. Charisma is your spellcasting ability for these spells.