If I play Stupefy during combat to reduce an opponent's unit below 4 might after they passed on playing an action, can they then play Cleave (which requires 4 might) after Stupefy resolves?

Ruling: Yes, after Stupefy resolves and you pass, if the opponent passes, then when Stupefy resolves they regain focus and can play Cleave at action speed. Combat doesn't end until both players have passed with focus and no chain (open showdown state).

Sequence:

• Opponent passes on playing an action with their 4 might unit
• You activate Stupefy (reducing their unit to 3 might)
• You pass
• Opponent passes
• Stupefy resolves (unit is now 3 might)
• Opponent regains focus and can now play Cleave at action speed

Nuances:

• Stupefy resolves first before Cleave can be played, since Cleave is at action speed not reaction speed