Does focus automatically pass to the opponent after a spell/action resolves, and can a player play actions back-to-back?

Ruling: Focus automatically passes to your opponent after a whole chain resolves (except the initial when I attack/defend chain). You cannot play actions back-to-back; your opponent must either pass focus back or play their action first.

Sequence:

• Player plays an action/spell
• The chain resolves completely
• Focus automatically passes to opponent
• Opponent must either pass focus back or play their action
• After opponent's action resolves, focus automatically passes back

Nuances:

• Two manual, consecutive passes of focus are still required to move on to the next step of the showdown
• The automatic focus pass after chain resolution is separate from the manual passing requirement