Omoplata From Guard When Opp. Raises Leg

Step 1: T raises one leg with both arms posted on B's body

Step 2: B uses their opposite side hand to break the grip on the lapel and get a sleeve grip on the arm on the same side as the raised leg

Step 3: B underhooks the raised leg with the same side arm and passes the sleeve grip to the underhooked arm

Step 4: B opens their guard and finishes the omoplata

OPTION II:

When B goes to finish the omoplata, they can put their free leg over the back of T's head to control T's posture. Sometimes T will grab the ankle of that leg and pull it off their head. B can break that grip and then go to a triangle choke instead.