Can you retreat a unit after damage has been assigned in a showdown?

Ruling: No, you cannot retreat a unit after damage has been assigned. Once damage assignment begins, damage is dealt and lethally damaged units are removed before any player receives priority to take actions like retreating.

Sequence:

• Damage is assigned in the showdown
• Damage is dealt simultaneously
• Lethally damaged units are removed in cleanup
• Players receive priority to take actions

Nuances:

• A unit that would be dealt lethal damage is not a valid target for retreat after damage assignment begins, as it will be removed before you can act