The Rick Roll
my basic response to any sort of shot is to turn and roll for the legs. but sometimes people are too defensive and they wont engage my legs. at times like those, the rick roll comes in handy. this technique is not difficult, but it requires you to train the instinct to sprawl completely out of your head. instead you invite the leg grab. you can do this on someone who shoots on you as well ( and i have with much success) but in this demonstration i'm going to show it from feeding them the leg.
the rick roll gets its namesake from a popular internet pass time of baiting someone with a cool link like:
Check out the trailer for the sweet new MMA movie coming out starring wanderlei silva!
and then laughing at them when they click it and get an ear full of Rick Astley.
this is the grappling version of this phenomenon.