Black Rose Wars is a competitive fantasy game of deck-building, strategy, and combat taking place in the hectic universe of Nova Aetas in Italy. Each player is a powerful mages of the Black Rose Order who seeks to become the new Supreme Magister to gain the mighty power of the Black Rose Artifact and the Forgotten Magic. Mages must fight, fulfill Black Rose desires, and gather strength with their spells until their power reaches the containment threshold of the prison where they are exiled, finally freeing themselves. Each mage has six schools of magic, each one with it's own strategy to annihilate their opponents and increase their power.

At the beginning of the battle, mages start with a grimoire of six cards; as mages study more spells during play, their grimoire increase. Every spell in Black Rose Wars has two unique effects, increasing a player's adaptability during a fight.

Mages battle each other in a modular arena of hexagons called "rooms". They summon powerful creatures, cast destructive spells, or devise dark deceptions with spells. The game system is divided into phases. Each turn, after selecting new spells from the six schools of magic, players plan their strategy in advance, placing cards face down. Later, they show the played cards to kill each other, solve missions, summon creatures, or destroy the prison rooms, one against each other and against the Black Rose (the playing system).

Once killed, mages are reborn immediately, allowing them to re-enter the fight without delay — although their death still fed energy to those mages who caused it.

The mage with the most power at the end of the fight will be crowned Supreme Magister of the Order by the Black Rose itself.