What does 'Open State' mean in Riftbound?

Ruling: Open State means the chain is empty. Actions can only be played when the chain is empty (in Open State), while reactions can be played any time you have priority.

Sequence:

• You gain priority when you get focus
• If you have the ability to play an action (focus and chain is empty), you also have priority to play reactions

Nuances:

• Actions can be played in showdowns when you have focus and the chain is empty, OR outside of showdowns on your turn when the chain is empty
• Reactions can be played any time you have priority, not just in Open State
• If there are actions in a chain, you can still play reactions as long as you have priority