Can you use Flash to move your unit away after an opponent plays Dragon Rage but before combat damage occurs?

Ruling: Yes, you can React with Flash while Dragon Rage is on the chain to move your unit back to base. If that was your only unit at the battlefield, the units won't deal damage to each other when Rage resolves.

Sequence:

• Opponent plays Dragon Rage (picks first unit and destination)
• While Rage is on the chain, you can React with Flash to move your unit back to base
• Dragon Rage resolves (opponent picks second unit)
• If you had only one unit at that battlefield, no damage occurs

Nuances:

• Dragon Rage only marks a showdown as pending if it moves a unit to the opponent's battlefield
• Dragon Rage does not start a showdown if moving a unit to a battlefield the caster already controls
• As of errata, Dragon Rage is reflexive and picks target units one at a time (first unit and destination, then after resolution, second unit)