When Zenith Blade is played on an attacking unit (Vayne) and a defending recruit, creating a combat showdown where neither side wins, which units are recalled and does anyone score?

Ruling: The attacker (Vayne) is recalled to base, and the defending player gains control of the battlefield and scores.

Sequence:

• Vayne moves, triggering an open showdown
• Zenith Blade is played
• Open showdown ends with no one scoring
• Combat showdown begins with Vayne as the attacker
• End of showdown: nobody dies, Vayne is recalled, and the defending player scores