Sorry if this has been asked before but I couldn't find the answer

If I attack a xwing with full shields, and decide to use vader does the crit bypass the shields? Or does the xwing just lose 1 shield token?

Vader deals 1 critical damage. You treat that the same way you do damage from any other source, so in the case of a X-Wing it loses 1 shield if it has any.

This is different from Proton Bomb, which says to deal 1 face up damage card to the ship. Those bypass shields because it's dealing a damage card rather then a critical damage.

Vanor is correct but think of it more as a guaranteed hit. And if you build your squad right you should have enough firepower at a higher PS to strip shields before your Doomcow (shuttle with Vader) shoots anyway.

Too tired to go look up precise wording, but I believe Vader uses the important key phrase along the lines of "to cause an opponent to suffer 1 critical damage." "...to suffer..." is the key phrase there; it refers you to the rules on Suffering Damage (someone can throw a page number out there), which refer you to checking for shields and removing those first, etc.

So yeah, Vader is just an automatic bonus critical damage symbol that takes effect once your attack has been resolved. Ideally you strip off shields with your actual attack and then bonus crit them when the defenses are out of Vader's way.

Thanks everyone

That's what I thought but just wanted to make sure

Also the damage vader does to his own ship takes off shields first too.