How do focus and priority work in Riftbound, specifically: what's the difference between them, how are they passed when a chain ends, and who gets focus first after the initial chain resolves?

Ruling: Focus is the ability to start a new chain during a showdown open state, while priority is the ability to play reactions to an existing chain. When the last item on a chain resolves, both focus and priority automatically pass to the next player.

Sequence:

• When a chain completes resolution, focus and priority automatically pass together (this is not an optional pass)
• The player who receives focus also receives priority
• Two consecutive optional passes are still required to resolve the next item or end the showdown
• After the initial chain resolves, the attacker retains focus (this is a confirmed rule correction - the current rules incorrectly imply the defender gets focus)
• Once a chain is established, the controller of the topmost item gets priority first
• When an item resolves mid-chain, the owner of the new topmost item gets priority again

Nuances:

• Priority is retained when playing a reaction, allowing multiple reactions in a row before passing
• If you pass priority after playing an action and your opponent also passes, the topmost item immediately resolves (both passed consecutively)
• You must react to your own spells immediately if you want to ensure you can do so even if your opponent doesn't react
• The automatic pass of focus when a chain resolves does NOT count toward the two consecutive passes needed to resolve items
• Starting a chain with a reaction as the attacker prevents your opponent from playing an action until that chain resolves, though you could usually just react to their action anyway
• Focus always remains with the attacker after the initial chain resolves entirely
• In multiplayer, focus passes to the next player in turn order, not just "the other player"