During an attack, if I play an action spell with focus, defender gets focus and plays nothing, do I get focus back?

Ruling: Yes, you get the focus back. Focus continues passing between players until all players pass focus in succession, at which point Showdown ends.

Sequence:

• Attacker gets focus and plays an action spell
• Defender gets focus (if no reactions played)
• If defender plays nothing, focus passes back to attacker
• This continues until all players pass focus in succession
• Then Showdown ends