"Re:|THM - Once upon a time" is a rhythm game RPG that travels through reversed time.

The rain rises from the bottom to the top, and defeated enemies come back to life. Meetings become separations, and the story heads towards the beginning.
Players will unravel the story of the separation of humans and monsters in reverse time. Experience the wonder of a world where time flows in reverse, something that cannot be experienced in reality.

The hero Astelro, who defeated the Monster King, kills the human king,
Ankh. Using the reverse device called "Ex" that only the king has, he reverses the flow of time.
What Astelro couldn't bear to lose even by going back in time...

Various wonders in reversed time

The story progresses like a video being played in reverse. The story is unraveled by looking back on the hero Astelro's regrets.
Will he sometimes be tormented by his past actions?

Real-time reverse rhythm game

The biggest feature of this work is a rhythm game that can be reversed in real-time. Even if you make a mistake, you can immediately roll back and restart from that point.