Can Imperial Decree kill units that survived combat and have already healed?

Ruling: Imperial Decree only kills units that are damaged after it resolves. It does not look back in time to kill units that were previously damaged but have since healed.

Nuances:

• Imperial Decree causes any unit that has any damage assigned to it to die
• The effect works both ways - your own units will also die from just 1 damage
• A strategy is to send units one by one to attack a populated battlefield to clear enemies one by one, since any damage will kill under Imperial Decree