How would you design a variable damage lasso weapon?

[martinaj]

I believe I'll be launching a, well, let's call it a "hometweaked" rather than a "homebrew" campaign that's going to be retooled to have a pretty heavy space western feel to it. Planning for a party of smugglers or outlaws or something, but one of their early (hopefully) recurring antagonist is going to be a hanging judge style Kasatha sheriff (who will join the Hellknights if he survives the early game), and I got an idea for a weapon I'd like him to have, but I want to keep it both cool and balanced.

Basically, he's going to use a pair of slug pistols and a cable lasso that he can use conventionally, or charge with electricity for stun and/or electric damage to subdue targets, create a laser edge around the inside of the loop for lethal attacks (which, in "cutscenes" could lead to some stylish executions).

But I am at a total loss at how I would stat such an item. Him being a boss level enemy, I don't mind if it feels kind of powerful or overbalanced, but I don't want to overdo it, and want to make sure it's useable and balanced if it ends up in the hands of my PCs.

[Ixal]

So basically the lasso from the 2nd Kingsman movie.

How about using capture poles as a start, make them ranged (but only a short range) and allow it to deal item level appropriate damage to someone grappled if the user uses an action?

[Metaphysician]

For flavor, have the lasso do Plasma damage, with the Stun property. If you want to take someone alive, that Plasma damage deals nonlethal, as its mostly electrical shock. If you want to kill someone, it deals lethal, and is less shock and more cut.