it says when you are dealt a face up damdage card flip it over

so i ama wondering is it

a) the ability is a one off?

b) the first critical hit of that combat phase is flipped over but all other critical hits are still face up

c) all critical hits are flipped face down

DarkGuard said:

The Chewbacca pilot card will flip all critical hits face down, so he is effectively immune to critical hits.

The Chewbacca copilot upgrade works differently and is a single-use card.

Thank you for answering my questions ( including the barrel roll question ) =D