334.1. The Active Player may do any the following:
334.1.a. Play a Card that is legally timed.
334.1.a.1. Cards , by default, cannot be played during a Closed State.
334.1.a.2. A Legally Timed Card would be a Card with Reaction.
334.1.a.3. Other exceptions may be created during regular play.
334.1.a.4. The card will be added to the chain as a Pending Item , following the steps of playing a card.
334.1.a.5. This can be an additional card to the item that Started the Chain in the case of the first Active Player after creating the Chain.
334.1.a.6. Whether a Card is legally timed is evaluated during the “Check Legality” step of Playing a Card. See rule 346. Playing Cards for more information.
334.1.a.7. Playing a card will create one or more Pending Items . Return to Step 1: Finalize.
334.1.b. Activate Abilities of Game Objects that are legally timed. See rule 386. Playing or Activating Abilities for more information.
334.1.b.1. All rules for legally timed cards apply to legally timed abilities.
334.1.b.2. Activating abilities will create one or more Pending Items . Return to Step 1: Finalize.
334.1.c. Pass Priority
334.1.c.1. The Active Player passes Priority to the next Player in Turn Order. Proceed to Step 3: Pass.