If you get a good dice roll (say range 1: {boom}, {boom}, & {kaboom}) be sure to remain patient! Let your opponent contemplate if they wish to modify their defense roll, if they're looking at having 1 shield left and two focus results and you jump the gun to indicate you would like to cancel all dice results to deal one facedown damage card they will still have that focus token you may have otherwise forced them into spending. Had you been patient they would've had to spend it to ensure that you had to cancel. Otherwise you would've been able to not cancel to take the shield and apply a facedown and faceup damage card to their ship.
Wampa with a {kaboom} is exciting because you get a great game effect, but be careful not to jump the gun and wait for all the steps to be completed for rolling and modifying to ensure you're stripping tokens when you can and/or doing extra damage when possible!!!