On topic, movie Boba is one of the coolest movie henchmen of all-time while also being the one of the most ineffectual.
The above points state his combat efficiency in Return of the Jedi: Mr. Fett struggled and was ultimately defeated to comedic effect by a Jedi waging a one-man battle against gangsters and a blind Han Solo trying to stop his friend from falling into a flesh-eating pit.
What happens when a six-foot-two killing machine starts stomping towards him while unloading submachine guns and shotguns with nothing but "terminate target" on its robotic brain?
If OP wants us to focus on OT canon feats alone, then Boba is pretty featless.
He can fly, he appears to have some (perhaps customized) E-11 Blaster Rifle (standard for Stormtroopers), nice wrist blaster, some rope to immobilize people with and a jetpack (which I mentioned already).
Boba could also be alive after Return of the Jedi, Nothing's been confirmed. An acid-damaged set of Mandalorian armor was discovered by someone within a Jawa sandcrawler.
As physically painful as this is to type, Jman is probably right. Boba doesn't even need to be proficient to win, the difference in armament spells doom for the T-800. What it basically boils down to is that bullets won't cut it against Star Wars metals, and blaster bolts will make short work of earth-steel. A clone trooper ought to have the advantage, too.
Hold on. A T-800's standard equipment would be a phased plasma rifle in the 40 watt range. Also, terminators are made of an alloy that can withstand extreme heat. The Terminator in T3 survived a plasma attack from the T-X, which was shown to be a lot more powerful than the average blaster in Star Wars. Arnold could probably take a few blaster shots before dying. I mean, Kylo Ren took a direct hit from a Chewie's bowcaster and he survived.
As impressive as that is physically (and it really is!) I think it's also at least implied that Kylo was channeling The Force to bolster himself. I don't think Boba Fett has that kind of connection to The Force, though Beskar has shown to be able to absorb a good amount of damage before its integrity is compromised.
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If you mean he was using the Force to keep himself alive that's possible. But if you mean he used the Force tank some of the shot then I have to disagree. He was focused on killing Han at that point. If a mere human can survive a blaster bolt a Terminator will have no problem tanking multiple shots.
I meant in keeping himself alive, assuredly. There was no way to look at that scene as the bolt from the bow caster doing anything but hitting directly, as I see it. I would argue it is a solid durability feat for Kylo physically as much as his skill in using The Force.
__________________ -"My internet is currently so bad I'm time traveling. Don't worry about it."
-"You have the best problems, Scenario. You really do. haermm"