When moving a unit to an enemy battlefield, can you play actions after your opponent responds with a spell, and what happens when that unit then moves to a second battlefield via Ride the Wind?

Ruling: You can play actions after your opponent's spell resolves because both players must pass focus in sequence before a showdown can end, so you always get an opportunity to play actions. When Darius moves to the second battlefield, a combat becomes staged there, but the first battlefield's showdown must finish before the second combat can start.

Sequence:

• Opponent's spell resolves and damages Darius
• You gain focus and can play Ride the Wind
• First battlefield showdown must complete (both players pass back-to-back before damage calculation)
• If first showdown was combat, damage clears from Darius when it ends
• Second battlefield combat can then begin
• You can continue playing actions/reactions as long as someone plays something and you receive focus

Nuances:

• Damage marked on Darius from the spell persists unless the first showdown was combat (in which case damage clears when that combat ends)
• Both players must pass focus back-to-back to move to damage calculation
• As long as someone plays something, you get passed focus again