When fighting Joker, he will occasionally cover Batman's face with poison goo, which you then have to swipe away. If you can remove the goo in less than 5 seconds, you earn the Last Laugh achievement. What's the best technique to quickly wipe away the goo? Is there anyway you can dodge the goo attack?
I finally earned this trophy. I used my index finger, extended across the entire screen, then wiped left-to-right in short quick strikes. It also seemed that pressing against the screen harder wiped more goo away.