In FFA4 (4-player free-for-all), how does the chain work during a showdown - can multiple players play Action speed cards, and how does priority/focus shift between players?

Ruling: In FFA4, only one Action speed card can normally be played per chain. Focus and priority shift between all 4 players in turn order starting from the attacker. Players can play as many Reactions as they want during their priority window, but only one Action card can start a chain.

Sequence:

• State is Open when chain is empty and Closed when chain is not empty
• Initial chain forms with triggers: Attacker's triggers > Other players' triggers in turn order > Defender's triggers
• Player with focus starts the chain with Action or Reaction
• That player can play Reactions (as many as they want)
• Priority passes to next player in turn order who can play Reactions (as many as they want)
• This continues through all players in turn order
• Priority cycles back to first player and continues in turn order
• Showdown ends only after all players pass focus in succession

Nuances:

• The initial chain rule (attacker > others > defender) only applies to triggered abilities at the beginning of combat ("When I attack...", "When I defend...", etc.)
• After the initial chain is formed, only turn order is used for priority
• Defender's triggers activate last but resolve first on the initial chain