A Crossover Story in the DC and Marvel Universes

A mysterious System from outer space descends upon Earth and randomly selects players to take part in a strange game:

"Card Game, but It's the ABO Version."

And so, in this room where "you can't leave until the game is over":

Bruce draws a card: "You are an Alpha. Each night, you have one chance to mark a player on the Omega team."

Dick draws a card: "You are a Nu. When a player on the Alpha team marks you, you can choose to mark them back."

Jason draws a card: "You are a Void. You can choose to be immune to marking, but there's a one-in-four chance that you'll go into heat and expose your identity."

Tim draws a card: "You are a Theta. You have only one single-use ability: you can mark anyone, but once you are marked, you can no longer use this ability."

Damian draws a card: "You are a Doma, a dual-star A..."

Damian's eyes widened in shock.

[System: Night has fallen. Players, close your eyes and enter the marking phase.]

[System: Day has broken. Players, open your eyes and enter the discussion and voting phase.]

Jason shouted angrily, "Someone marked me last night! Who was it?"

Dick smiled. "Jason, you know that if I were an Alpha, I definitely wouldn't mark anyone in the first round."

Tim calmly said, "Jason, you know me. If I were an Alpha, you definitely wouldn't be the first person I'd mark."

Damian gritted his teeth. "If I were an Alpha, none of you would escape being marked!"

Bruce: "..." The kids had already said it all. What was he supposed to say?

Warning:

This is a card-game story. At its core, it's about family and friendship, with no romantic pairings.

The game rules will be explained in the story, but the games are basically card games adapted from ABO genders.

In this setting, A, B, and O are three kinds of "player teams," and the 24 genders correspond to 24 identity cards.

Please cherish the characters. The System is the root of all evil.

Theme: Keep going.