Historical Rules · 18 June 2010
Rule 903.5
Official source text from the 18 June 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.