Never Mind, I figured it out. Discard the card to add X hits the the attack.
Unsure how to play the Ambush card in the Pathfinder class (as an example)
Do I have a permanent Strike 2 when the skill is prepared until it is discarded?
"When an enemy moves into a space, you may discard this skill to attack that enemy, if possible, add 1 success to the test.
Strike 2 "
Edited by Thaeggan