I am playing Vader with ATC. I roll two hits and have a target lock. So now do I add a critical hit for a 3rd hit. Or do i change one to a crit?

ADD a crit.

But remember you can't spend the target lock. You just need it to gain that extra critical result.

If you miss with the two normal shots, do you still get the crit?

Yes. You may a [KABOOM] die roll, as long as you don't spend the Target Lock. when you roll your Attack, so it doesn't matter what your roll is. You just cannot use your Target Lock if you add the die.

It is probably worth reminding people that you CAN choose to not get the auto crit and spend the target lock as normal. I've done that with Vader a couple times, gotten to range one with TL and focus, roll 3 dice, get 3 blanks, REALLY want 2 damage so spend the TL instead of add the auto crit and hope to roll better than 1.

Its real easy to get into the mindset with ATC that your TL cannot be spent at all, and that isn't the case.

Here's the list that just won New Zealand Nationals over the weekend.

36 points: Darth Vader TIE Advanced, TIE/x1, Lone Wolf, Engine Upgrade, Advanced Targeting Computer.
39 points: “Whisper” TIE Phantom, Fire-Control System, Veteran Instincts, Advanced Cloaking Device.
24 points: Lieutenant Colzet TIE Advanced, TIE/x1, Advanced Targeting Computer.

Seems the ATC is popular.

The 3rd and 5th place winners had Darth with a similar loadout.

I've been having fun with:

Darth Vader (29)

Predator (3)

Advanced Targeting Computer (1)

Twin Ion Engine Mk. II (1)

TIE/x1 (0)

Juno Eclipse (28)

Push the Limit (3)

Advanced Targeting Computer (1)

Twin Ion Engine Mk. II (1)

TIE/x1 (0)

"Zeta Ace" (18)

Epsilon Squadron Pilot (15)

Total: 100

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