If my opponent attacks a battlefield where I have a unit and plays Rebuke (which resolves), can I then play Zenith Blade to move another unit from base into the showdown?

Ruling: Yes, you can play Zenith Blade after Rebuke resolves. You will stun one of their attackers, then move a unit into the showdown where it becomes a defender.

Sequence:

• Rebuke resolves
• You play Zenith Blade on your action
• Stun one of their attackers
• Move a unit into the showdown
• The unit becomes a defender

Nuances:

• Showdowns and combat do not end until both players fully pass focus
• You cannot lose control of a battlefield while a combat is happening