Can you use Arcane Shift to replay a banished friendly unit back to a contested battlefield you are attacking during combat?

Ruling: No, you cannot replay the unit to the contested battlefield you are attacking. As the attacker, you do not control that battlefield—the defender does, even while contested. You can only play the unit to your base or to a battlefield you control.

Sequence:

• The unit is banished from the contested battlefield
• You must play it to either your base or a different battlefield you control
• If played to a battlefield during showdown, the unit enters exhausted and gains attacker/defender designation during the cleanup phase

Nuances:

• Arcane Shift can be played during showdowns, but the replayed unit must go to a legal location
• A player maintains control of their battlefield while it is being contested by an opponent
• This is different from a Recall effect, which would specifically force the unit to return to your base