Chaotic Good

t-rex isn't exactly known for being able to take things

I mean, in defense of the t-rex, it's not it's it's arms that are grabbing whatever it is, it's their maw. Try resisting a t-rex trying to get something off your hands with it's teethy mouth you're not gonna have arms left to resist.

But then you could, in this hypothetical scenario, argue that it'd be more equal then. Neither of you would have useful arms to fight with.

I'm betting on the t-rex in a mouth-combat match.

Even with a bunch of guns, I bet a t-rex could sustain more bullets than a human could sustain one nibble from a t-rex mouf.

E: and I bet you could teach a t-rex to shoot a firearm even if it couldn't aim that well. So an armed t-rex would definitely win.