Shahrazad

Set
Arabian Nights
Rarity
Rare
Text
Players play a Magic subgame, using their libraries as their decks. Each player who doesn't win the subgame loses half their life, rounded up.
Legality
Banned in: Commander, Duel, Legacy, Vintage
Legal in: Oldschool
Rulings
2004-10-04: At the start of the sub-game both players draw their initial hand (usually 7 cards). If one player has fewer cards than required, that player loses. If both have fewer than required, both players lose.

2004-10-04: Events in a Shahrazad sub-game do not normally trigger abilities in the main game. And continuous effects in the main game do not carry over into the sub-game.

2004-10-04: You randomly chose which player chooses to go first or draw first.

2007-07-15: At the end of a subgame, each player puts all cards they own that are in the subgame into their library in the main game, then shuffles them. This includes cards in the subgame’s Exile zone.