When Hidden Blade is played from hand during a showdown, does it kill the unit before damage is calculated?

Ruling: Yes, Hidden Blade kills the unit before damage is calculated. Spells resolve before combat damage is dealt.

Sequence:

• Hidden Blade is played during showdown
• The spell resolves, killing the target unit
• Combat damage is dealt (after the showdown is over)
• Since the unit is already dead, it does not deal or receive combat damage