Rule 305.1

A player who has priority may play a land card from his or her hand during a main phase of his or her turn when the stack is empty. Playing a land is a special action; it doesn’t use the stack (see rule 115). Rather, the player simply puts the land onto the battlefield. Since the land doesn’t go on the stack, it is never a spell, and players can’t respond to it with instants or activated abilities.

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