So on backdraft's pilot ability he can add a crit when attacking in the auxiliary arc.

Does that mean adds a whole new die?

thanks for help

Yes.

Yes. You add an additional dice to the pool. This is functionally identical to things like adding an evade to the dice pool by spending an evade token. These are considered modifications.

For clarity, note that abilities that change an existing dice explicitly say so. For example: "You may change 1 die result to a [Hit]" rather than "You may add a [Hit] result"

Thanks very much for the info

So on backdraft's pilot ability he can add a crit when attacking in the auxiliary arc.

Does that mean adds a whole new die?

thanks for help

Yes, but be aware it adds that die after the initial roll and during the Attacker Modifies Attack Dice step. So you roll your basic 2 attack dice, the defender has the opportunity to modify those two dice if he can, and then you add the new die with the crit result showing, and you can modify any of those three dice how you see fit.