Meng/
Haku's Tongan Death Grip, although invariably it led to a pin rather than a submission there was the odd time (i.e. submission only bouts) where it got the submission. So simple, but when sold properly it was pretty cool, mainly because people bought Meng as a tough guy, probably because by all accounts he is a legit tough guy, and now he's a car salesman to

(I think)