Anu

Anu was a central deity in ancient Mesopotamian religion, especially in Sumerian, Akkadian, Assyrian, and Babylonian traditions. Known as the supreme sky god, Anu was considered the father of the gods and the divine authority behind kingship and cosmic order. Worshiped as early as the 3rd millennium BCE, his primary cult center was the city of Uruk. Although later mythologies elevated gods like Enlil and Marduk to more active roles, Anu remained the symbolic embodiment of the heavens and ultimate divine power.

Pop Culture and other references: None that I know of directly.

BASIC Astral Burst
Attack 1 enemy (200%DEF + 100%ATK). Place [Vanish] on the ally with the lowest current HP for 1 Turn.
Awakening I: Also place [Stalwart] on the ally with the lowest current HP for 2 turns.

CORE Cooldown 5 Grace of the Heavens
Place [DEF Up II] on all allies for 2 turns and {Protect II} on all allies except this hero for 2 turns.
Awakening V: Allies under [Protect] cannot receive critical hits.

ULTIMATE 1000 Cosmic Salvation
Place [Phoenix] on all allies for 2 turns, then all allies except this hero will attack 1 target enemy. If an ally is under {Protect II}, they will Heal for 30% of the damage inflicted.
Awakening III: Allies will convert 100% of the excess healing into a [Shield].

PASSIVE Celestial Ward
For every 10% Divinity on this hero, reduce the damage allies receives by 3%.

LEADER 30% DEF Arena Battles

IMPRINT Celestial Ward
For every 10% Divinity on this hero, reduce the damage this hero receives by 1.5%.
Source: Fateless Videos