If I hold a battlefield with one unit and move it back to base, can I play a unit there?

Ruling: No, you cannot play a unit there after moving your only unit back to base because you are no longer in control of that battlefield.

Sequence:

• When you move your only unit back to base, you lose control of the battlefield
• Cleanup happens after a unit is moved
• Hidden cards at that battlefield would be discarded during cleanup if no other unit is played there first
• To maintain control, you must play another unit at the battlefield before moving the original unit back to base

Nuances:

• During a showdown, if your last unit is killed, hidden cards stay until the opponent contests the battlefield or passes
• Outside a showdown, once you lose your last unit you lose control immediately
• Cleanup also happens after every item on the chain resolves