The awesome thing about Batman: Arkham Asylum, could very well be its fighting mechanics. Unlike other Batman games in the past, you're able to use combos in order to take out baddies that may get in your way. These come in handy whenever you're fighting thugs that have been sent by the Joker. You can reach a 5x, 10x, 20x, and even 40x combo. So, for reaching such a feat, you'll be rewarded with some gamer points. In this tutorial, you'll find out how to unlock the Freeflow Combo 40x achievement. Good luck and enjoy kicking some butt!