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Historical Rules · 1 February 2010

Rule 903.5

Official source text from the 1 February 2010 Rules release

At the start of the game, each player puts his or her general face up next to his or her library. The generals start the game in the command zone. Then each player shuffles the remaining 99 cards of his or her deck so that the cards are in a random order. Those cards become the player's library.

Find this number in the current Rules