Hi folks, short question: Can I spend more damage to deal more crits per round. Let's say if my sill still has enough hull? Thanks Alex.

This would be so OP if you could. You can only use once per round.

An ability can only be used once per opportunity. However, gunner does provide a second opportunity, provided you miss the first time

Cluster missiles and gunner allow three attacks, triggering Vader three times.

The Imperial Raider can attack up to eight times during one round, allowing Vader to nearly tear it apart with 16 points of damage.