When Player A moves to an empty battlefield to conquer, and Player B uses Ride the Wind to move to that same battlefield during their action opportunity, who is the attacker and who is the defender?

Ruling: The attacker designation goes to whoever applied contested to the battlefield first. In this case, Player A is the attacker because they applied contested when they first moved in.

Sequence:

• Player A moves to empty battlefield, applying contested status
• Player B uses Ride the Wind to move to the same battlefield, staging combat to occur after the current non-combat showdown
• Since control can't be established in the non-combat showdown (two players have units there), it remains contested in the combat showdown
• The contested designation carries over, keeping Player A as the attacker