Can a player declare a reaction after both players have passed on playing spells in a row during a showdown?

Ruling: No, a player cannot declare a reaction after both players have passed on playing spells in a row during a showdown. Once both players pass consecutively on Focus, the showdown concludes and the game moves to assigning damage.

Sequence:

• Players declare spells during the showdown
• If both players pass on Focus in a row, the showdown concludes
• The game moves to assigning damage
• No reactions can be declared after this point