When playing Blitzcrank to an open battlefield and hooking an enemy unit, who is the attacker and who is the defender in the resulting showdown?

Ruling: When you play Blitzcrank to an open battlefield (using an ability like purple Miss Fortune) and hook an enemy unit, you are the attacker because your unit applied the Contested status to the battlefield first.

Sequence:

• You play Blitzcrank to the open battlefield
• The showdown is marked as pending
• Blitzcrank's hook ability resolves, pulling an enemy unit to the battlefield
• When the chain resolves, the showdown starts
• You are the attacker because Blitzcrank applied the Contested status first

Nuances:

• You need an ability like purple Miss Fortune to play a unit to an open battlefield in the first place
• If you play Blitzcrank to a battlefield you already control, the enemy unit causes the Contested status, making you the defender instead