Some of the best submissions in grappling are based on the catch-as-a-catch-can principle which means if you can get, it to work, you should. The Scorpion Lock shoulder lock submission is one such submission, especially when set up from back control.
If you want people to be surprised when you attack a submission, do not do the submission that they expect you go for from s specific position. For example, you don’t have to only look for a rear naked choke from back control when you can easily switch things up and add surprise submissions like the Scorpion Lock from the same position.
The Scorpion Lock works off of a rear-naked choke threat, which is one of the reasons why this shoulder lock has such a high percentage finishing rate. As an opponent is using both their arms to defend a rear-naked choke, you use their actions against them.
The first thing to do is place the foot of the leg which is on the side opposite of your choking arm on the hip of your opponent. This provides ample space for you to sneak your free arm in over their shoulder as if you were switching arms for the choke.
Instead of choking, though, you will circle your arm to the outside, trapping the opponent’s wrist in your armpit. This puts the opponent’s arm in the Scorpion Lock position, which is essentially an Americana lock, just done from a weird angle.
For the finish, turn into your opponent with your entire upper body. It is important to resist the urge to extend your hips and lie backward, as this will help the opponent get the arm out, instead of placing pressure on their shoulder. As long as their elbow goes forward while you have the wrist trapped, the Scorpion Lock is going to work and break the opponent’s shoulder.