When Player 1 moves a unit into an uncontrolled battlefield creating a neutral showdown, then Player 2 casts Ride the Wind to move a unit into that same battlefield during Player 1's pass window, who is the attacker and who is the defender in the resulting combat?

Ruling: Player 1 is the attacker because they applied contested status to the battlefield. Player 2 is the defender and benefits from Shield and defender triggers (known as a "surprise defence").

Sequence:

• Player 1 moves a unit into an uncontrolled battlefield, creating a neutral showdown
• Player 2 casts Ride the Wind during Player 1's pass window, moving their unit into the same battlefield
• The current showdown continues until both players pass on an empty chain with focus (staged combat)
• Once the first showdown is over, the staged combat becomes a regular combat
• Player 1 is attacker, Player 2 is defender

Nuances:

• The first showdown is not a combat because only one player's units were present when it was initiated
• There will be no "combat" from the first showdown, only from the second showdown after both players have units present