What happens if Zenith Blade is played targeting an enemy unit at a battlefield, and the opponent responds by recalling that unit with Flash before Zenith Blade resolves?

Ruling: Zenith Blade loses its target and does nothing. The card requires targeting an enemy unit at a battlefield, and if that unit is no longer at a battlefield when the spell resolves, the targeting condition fails and neither effect (stun nor moving a friendly unit) occurs.

Nuances:

• Zenith Blade does not separately target the battlefield itself; it only targets the enemy unit at a battlefield
• The second effect references "that enemy unit's battlefield" which no longer exists if the unit is recalled
• All targets are declared when the spell is cast, but the targeting condition must still be valid when the spell resolves