Three years before the events of Yggdra Union, the kingdom of Bronquia is in the midst of a dark age under a greedy king whose ineffective rule leaves the population struggling. The main character, Garlot, is a member of a group of noble thieves along with his friends. Their group catches the eye of a local noble who begs the group to find a way to stabilize the kingdom before it collapses.

This entry in Sting's Dept. Heaven series picks up where Yggdra Union left off gameplay-wise, continuing its unique blend of card game, turn-based strategy and real time strategy. Blaze Union introduces three new cards. It also features a branching narrative, with three total endings depending on the player's choices.