Coming soon

About This Game

Who Must You Defeat—the Demon King, or God?

One day, a voice from nowhere calls to you, drawing you into the story of girls who bear the names of birthstones.

On nights of the full moon, you are 《God》.

On nights of the new moon, you are the 《Demon King》.

Move freely between both sides,

and awaken the true power of the girls divided between light and darkness.

Advance Preview Scope

The current Steam advance preview includes:

• God- and Demon-side story Chapters 1–3

• Demon-side tower defense stages 1-1 through 1-10

• God/Demon side switching, character growth, and 4v4 battles

• The castle town, demon-castle prosperity, and taskbar-style companion

The following content is in development for the full release and is not included in the advance preview: Chapter 4 onward, TD 1-11 onward, the Magic Racetrack, the outside map/gathering/vehicles/garage, and seasonal event hubs.

A World That Grows While You Play

Keep a lightweight companion open beside your taskbar and check in between work—or another game. The God-side companion follows your pilgrimage and idle exploration, while the Demon-side companion tracks castle production and development.

You do not need to stay glued to the screen. Collect what has accumulated, set your next direction, and return to your day. When you want a more active session, open the full game for 4v4 battles, story chapters, and tower defense.

• Two lightweight companions — Keep an eye on the God and Demon King sides, even side by side

• Progress through short check-ins — Review exploration rewards, resources, and construction when it suits you

• Growth that carries into the full game — Build momentum in the small window, then return for battles and story

A God at the Full Moon. A Demon King at the New Moon.

Two parcels arrive from a prize campaign he does not remember entering. Inside: two birthstones and a QR code.

On the night of the full moon, an ordinary young man is pulled into another world as a bodiless God. He resonates with the birthstone heroines, sharing their senses and awakening powers neither could wield alone. At the new moon, the same protagonist is called to a second role: the Demon King.

Are light and darkness truly the same as good and evil? The God meant to save the world enters the Demon Castle and orders construction instead of destruction. Even the “enemy” has a home worth protecting.

God Side — Raise the Twelve Envoys for 4v4 Battles

Recruit the Twelve Birthstone Envoys and shape their growth through levels, equipment, skills, and awakening. Build a team whose roles work together, then lead them into 4v4 battles.

• Twelve memorable companions — Each birthstone brings a different personality, role, and story

• Growth and team building — Combine levels, equipment, skills, and awakening

• Costume customization — Choose seasonal and themed looks for your favorites

• 4v4 battles — Plan your frontline, support, and reserves to build a team of your own

Demon Side — Build a Realm Worth Defending

Gather nine resources, construct facilities, and develop the castle town. Your Demon Castle is more than a battlefield: it is a living realm with homes to protect and a future to build.

• Demon Castle Prosperity — Resource production, facilities, castle levels, and a branching development road

• Castle town development — Visit specialized districts, develop facilities, and help the realm prosper

• Star-Ring Defense — Spend DP to deploy characters and summoned units, then protect your cores against incoming waves

Twelve Birthstones. Two Faces of Fate.

Under the full moon stand the Twelve Envoys of Light. Under the new moon wait the Twelve Generals of Darkness. The same birthstones reveal different faces when their loyalties and destinies change.

Keep it small on busy days. Dive deep when you have time. Re:BirthStone is designed as two worlds that keep growing beside your everyday life.

AI Generated Content Disclosure

The developers describe how their game uses AI Generated Content like this:

Some pre-generated artwork and visual assets used in the game and its store and marketing materials were created with generative AI tools, then selected, edited, and integrated by the development team. The game does not generate AI content during gameplay and does not connect to external AI services while you play.