For the sake of the record books let it be known that Badassasaurus Rex is one of my most utterly despised bosses in history as of now.
Even when hiding back behind cover and cherry-tapping him to death the frikkin' robodinosaur of doom managed to kill me once, effectively forcing me to lose all 400 stacks of Anarchy that I went to the mind-numbing trouble of farming for the singular goal of fighting the goddam roborex in the first place. So I had to cherry-tap him to death with much lower damage because there was no way I was gonna make the trip to Sanctuary to amass another 400 stacks before trekking back and starting the process over. Eff that.
Aside from the constant barrages of homing missiles and one-hit kill nukes the thing has enhanced defense against all damage except explosion damage, and has the added bonus of shots getting reflected back at you. Even the 'splosive ones. that sucks, because it means even a single stray bullet that I shot can wind up reflecting back at me and cutting through my shields.
It was just such a tedious and unrewarding fight, and the loot it dropped wasn't even that good.
Killing Piston was pathetically easy and incredibly satisfying, though.
Anyway, point of the story being a robot t-rex killed me
again.
Borderlands 2
The loot from the vault was pretty lame too.