103.1 At the start of a game, each player shuffles his or her deck so that the cards are in a random order. Each player may then shuffle or cut his or her opponents’ decks. The players’ decks become their libraries.
103.1a If a player is using a sideboard (see rule 100.4) or cards being represented by checklist cards (see rule 713), those cards are set aside before shuffling.
103.1b In a Commander game, each player puts his or her commander from his or her deck face up into the command zone before shuffling. See rule 903.6.
103.1c In a Conspiracy Draft game, each player puts any number of conspiracy cards from his or her sideboard into the command zone before shuffling. See rule 905.4.
103.2 After the decks have been shuffled, the players determine which one of them will choose who takes the first turn. In the first game of a match (including a single-game match), the players may use any mutually agreeable method (flipping a coin, rolling dice, etc.) to do so. In a match of several games, the loser of the previous game chooses who takes the first turn. If the previous game was a draw, the player who made the choice in that game makes the choice in this game. The player chosen to take the first turn is the starting player. The game’s default turn order begins with the starting player and proceeds clockwise.
103.2a In a game using the shared team turns option, there is a starting team rather than a starting player.
103.2b In an Archenemy game, these methods aren’t used to determine who takes the first turn. Rather, the archenemy takes the first turn.
103.2c One card, Power Play, states that its controller is the starting player. This effect supersedes these methods.
103.3 Each player begins the game with a starting life total of 20. Some variant games have different starting life totals.
103.3a In a Two-Headed Giant game, each team’s starting life total is 30.
103.3b In a Vanguard game, each player’s starting life total is 20 plus or minus the life modifier of his or her vanguard card.
103.3c In a Commander game, each player’s starting life total is 40.
103.3d In an Archenemy game, the archenemy’s starting life total is 40.
103.4 Each player draws a number of cards equal to his or her starting hand size, which is normally seven. (Some effects can modify a player’s starting hand size.) A player who is dissatisfied with his or her initial hand may take a mulligan. First, the starting player declares whether or not he or she will take a mulligan. Then each other player in turn order does the same. Once each player has made a declaration, all players who decided to take mulligans do so at the same time. To take a mulligan, a player shuffles his or her hand back into his or her library, then draws a new hand of one fewer cards than he or she had before. If a player kept his or her hand of cards, those cards become the player’s opening hand, and that player may not take any further mulligans. This process is then repeated until no player takes a mulligan. (Note that if a player’s hand size reaches zero cards, that player must keep that hand.) After all players have kept an opening hand, each player in turn order whose hand contains fewer cards than that player’s starting hand size may look at the top card of his or her library. If a player does, that player may put that card on the bottom of his or her library.
103.4a In a Vanguard game, each player’s starting hand size is seven plus or minus the hand modifier of his or her vanguard card.
103.4b If an effect allows a player to perform an action "any time [that player] could mulligan," the player may perform that action at a time he or she would declare whether or not he or she will take a mulligan. This need not be in the first round of mulligans. Other players may have already made their mulligan declarations by the time the player has the option to perform this action. If the player performs the action, he or she then declares whether or not he or she will take a mulligan.
103.4c In a multiplayer game, the first time a player takes a mulligan, he or she draws a new hand of as many cards as he or she had before. Subsequent hands decrease by one card as normal.
103.4d In a multiplayer game using the shared team turns option, first each player on the starting team declares whether or not he or she will take a mulligan, then the players on each other team in turn order do the same. Teammates may consult while making their decisions. Then all mulligans are taken at the same time. A player may take a mulligan even after his or her teammate has decided to keep his or her opening hand.
103.5 Some cards allow a player to take actions with them from his or her opening hand. Once the mulligan process (see rule 103.4) is complete, the starting player may take any such actions in any order. Then each other player in turn order may do the same.
103.5a If a card allows a player to begin the game with that card on the battlefield, the player taking this action puts that card onto the battlefield.
103.5b If a card allows a player to reveal it from his or her opening hand, the player taking this action does so. The card remains revealed until the first turn begins. Each card may be revealed this way only once.
103.5c In a multiplayer game using the shared team turns option, first each player on the starting team, in whatever order that team likes, may take such actions. Teammates may consult while making their decisions. Then each player on each other team in turn order does the same.
103.6 In a Planechase game, the starting player moves the top card of his or her planar deck off that planar deck and turns it face up. If it’s a plane card, that card is the starting plane. If it’s a phenomenon card, the player puts that card on the bottom of his or her planar deck and repeats this process until a plane card is turned face up. (See rule 901, "Planechase.")
103.7 The starting player takes his or her first turn.
103.7a In a two-player game, the player who plays first skips the draw step (see rule 504, "Draw Step") of his or her first turn.
103.7b In a Two-Headed Giant game, the team who plays first skips the draw step of their first turn.
103.7c In all other multiplayer games, no player skips the draw step of his or her first turn.