Created by Makenzie De Armas, Asteria is a princess-turned-paladin who assisted in the making of The Deck of Many Things.

Introduced in The Book of Many Things, Asteria is an autistic paladin who suffers from sensory overload and other common manifestations of the disorder. She was described by designer Makenzie De Armas in an interview with Polygon.

You can read more about The Book of Many Things below:

Introduce more magical whimsy into your game with The Book of Many Things. Dive deeper than ever before into the lore behind the beloved magic item, the Deck of Many Things. How did it come to be? What is the significance of one baneful figure depicted in the cards? The answers you seek – and more – will be revealed for the first time ever.

The Book of Many Things Illuminates the deck’s mysteries and provides everything Dungeon Masters & players need to use them in their campaigns. This book includes cosmic character options, adventure locations, mysterious organizations, mystic monsters, and more; all inspired by the deck.

• Create mystic characters with 2 new backgrounds, 1 feat, and 3 mystical spells in the D&D Beyond character builder
• Clash with over 30 new mystical monsters in the D&D Beyond Encounter Builder
• Uncover 50+ new magic items inspired by the cards
• Offers tools for DMs like traps, location maps, & more

For those unfamiliar, The Deck of Many Things is a magical item in Dungeons and Dragons, which comes in the form of a deck of cards. Each card causes a different effect on whoever draws it out, which range from having a wish granted to being put in a catatonic state as your soul leaves your body.

This may also be a historical retcon depending on who Asteria is. The Deck of Many Things was originally introduced in the 1975 Greyhawk supplement, though it was said to also exist in the Forgotten Realms campaign setting as a Netherese artifact called The Deck of Hazards.

Forgotten Realms is the default campaign setting for Dungeons & Dragons 5th Edition and the setting for the Baldur’s Gate franchise.

You can pre-order The Deck of Many Things digital + physical bundle on the official Dungeons and Dragons site. It includes physical versions of The Book of Many Things, The Deck of Many Things, and seemingly a lot of retcons.