2 Part Technique - Your opponent may realize that you need an underhook to pass his half guard, but he'll likely forget to protect both of his sides for it. Try to flatten out his underhook on the side of the half guard, and when the opening presents itself, pummel for the underhook on the opposite side of his figure-four around your leg. Continue to hold him flat, reaching around for his head and connecting with the Reverse Underhook & Head Control. Use your weight to knock his hips to the side of your crossface and drives your far knee across his thigh, kicking your foot free with your shin if need be. If his half guard is too secure for the Knee Cross Pass, throw your nearside hip over his body onto the mat while still locked in his half. After this Back Step, use your shin once again to help pry off his remaining guard for the pass.