Artemis BJJ (MYGYM Bristol), Can Sönmez, Bristol, UK - 08/07/2016
To pass the open guard, it is advisable to grip on the inside of both their knees for control (though not everyone would agree on that: others suggest gripping lower on the trousers by their shin, knuckles facing forward, or even at the bottom of the trousers). The main danger is that they will try to loop their leg over your arm, which you can mitigate by gripping a little lower than the knee. If their legs are raised, twist your elbows in, so that your forearms are parallel to their lower legs. Be sure to keep your elbows inside their knees: if they do manage to loop an arm, you may need to release and then re-grip back inside their knee.
That means you can then start to move their legs in several directions. There are many variations of the bullfighter pass (also called the toreador, toreana, toreada, toreando and matador, among other names. Google tells me the Portuguese for bullfighter is in fact 'toureiro'), but I think the simplest is to step back when you have that grip, so that the soles of their feet press into the floor. Straighten your arms and lean through them, so that all your weight is punching downwards towards the mat.
The aim is to prevent them being able to move their legs, so that you can now walk around before they are able to recover. Keep your base wide, plenty of space between your feet. As soon as you get past their knees, turn slightly and drop your leading shoulder into their hip. Stay on your toes all the way through: if you go to your knees, that immediately reduces the pressure on your opponent.
After you make contact with your shoulder, maintain at least one grip on their leg, as otherwise they may be able to start to recover by getting a leg in the way. Bring the knee nearest to their legs into their hip, then release one grip in order to bring an elbow around their far hip. It's important that you restrict their ability to move their hips, as otherwise they will start trying to shrimp away from you. From there, you can establish side control, or potentially move through into mount.
Teaching Notes: I got injured again, which messes me up. Freak injury from sparring, bashed heel. Gah. Anyway, I'm pretty happy with this pass. Main defence is to sit up, but as long as you keep everything pinned, you can still drop your shoulder and pass. I added in a drill just doing that drop, which I think helped. I didn't see as many people go to their knee first on this. Just one variation of the bullfighter of course, there are loads of others.