If a unit is dealt lethal damage by a spell during a showdown, does it die before being able to deal combat damage?

Ruling: Yes, the unit dies before dealing combat damage. A cleanup happens after the spell resolves, killing units with damage greater than or equal to their might. Combat damage only happens at the end of the showdown after both players pass focus in sequence.

Sequence:

• Spell resolves and deals damage to the unit
• Cleanup occurs automatically, killing units with lethal damage
• Combat damage happens later at the end of the showdown (after both players pass focus in sequence)

Nuances:

• The killed unit never gets to deal its combat damage since it dies during the cleanup before the combat damage step