When I think of two Submission holds I loved watching.. it goes without saying..
Edgucator
Basically a reverse/inverted Sharpshooter. Edge doesn't use this move nearly as much as he truly needs to, and it could in all honesty boost him even higher upon returning, to go back to this as a top finisher to use.
The hold is the best of both worlds as far as submissions go. Its an inescapable hold, and its not forcing you to turn your back to your opponent, or give up any type of body part to be attacked in chance of a reversal.
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While that version wasn't the full effect version he's used to make opponents tap out, even as you can see within the video the submission move is inescapable and your opponent's only hope is to reach the ropes. The bit I find funny the most is, in the better versions of the hold, Edge sits down deeper in it, putting more arch and pressure on the opponent's back.
Once again, this is a prime finisher that I believe Edge should return to and it was always great to see it used. I was disheartened to see Edge begin using the Sharpshooter, but believed that it was only due to so many workers/opponents not knowing how to properly work with this type of move. Thats how unique it was.
Tazmission
In the words of Kurt Angle..
"Thats not a submission, its an illegal choke!" Well, whatever it is.. its fucking useful! I can say without question this is a great submission hold, and from personal experience.

I once locked this bad boy in on someone and they flat out turned fucking dark red in the face.
Whenever I seen Taz use this, it felt vastly more superior than a regular rear naked choke. Maybe it was the energy and excitement Taz put behind it, maybe it was always the fans eruption whenever the submission was locked in. I'll never fully know. But one thing is for sure, this submission hold is amazing.