406. Play

406.1. A player Plays cards by paying costs associated with that card. See rule 346. Playing Cards for more information.

406.2. This is a Discretionary Action.

406.2.a. As long as a player has the resources to pay the costs associated with the card, they may play cards.

406.3. Game effects may result in cards being played as part of their resolution.

406.3.a. This treats Play as a Limited Action.
406.3.b. Treat all steps of Play as normal, except as noted by the game effect creating this Limited Play Effect.
406.3.c. If there are no eligible cards to Play when instructed to Play in this manner like this, then nothing happens and resolution continues.

406.4. Some Abilities trigger when cards are played or otherwise check whether cards have been played.

406.4.a. These abilities trigger when the act of playing the card has been completed by the resolution of the card.
406.4.b. If a game effect prevents the resolution of the card—for example, because the card was countered —the card wasn't played and no abilities that trigger on playing cards trigger. See rule 412. Counter for more information.