A few times. Here and there. Less and less as BH got progressed. He was kind of hard to put down, to be honest, once he got the heal posse goin'. (Heal posse is what I called the 15-20 minions that would follow me around providing healing power due to... um... whatever the power that does that in Willpower set...) I'd start with a couple, then not defeat them and they'd follow... I'd target mostly LTs, Bosses, and the occasional GMs like Fake Nemesis when he came into the zone, stuff like that.
Then later as he got to 50+ and incarnate, well, he'd just stand at a Rikti Pylon and they'd just go at it, him punching the pylon, the pylon trying to take him down... Fun lil' standoff.
Sappers were to be taken out immediately, of course, can't have them shuttin' me down. Cimerorans were the only real problem other than that (and AVs, GMs, and such) because of their ability to put so much -DEF on him, but he did ok with them.
Frequently I'd just leave him sitting in the middle of a posse, get up, do something, come back... and there he was, just being pummeled on but nothing happening. All the heal, all the endurance, ALL THE THINGS, including Psi defense. Brawl only lets you go full defense as you can get.
As far as difficulty? Ain't no difficulty when you're street sweeping no missions. That said, somewhere about 20-25ish? I was intentionally going after +6 everything possible, and as big a group as I could get in. Multiple bosses and lieutenants, and I'd hit the LTs first then the bosses, which mitigated damages faster. Unless there was a sapper or such. It was kind of a power trip, to be honest. ð
BH died quite a few times for The Honoree. That mission was much difficult. But I kept at it. Eventually figured it out and got through it solo!
Then there was whatever mission where you're going after Chimera. He was the most difficult thing I did in the game. This mission went on start to stop for an hour for BH. Chimera went from a +0 EB to a +3 EB, and let me tell you, he was *tough*. But the map was big enough I could escape, rethink, try something else, almost but not quite be defeated, retreat, keep trying... and then I figured it out. The first part took me 30 minutes of goin in, back out, resting up, go again to get it figured out, then it took another 30 minutes of constant technique, almost dyin', but at the end I won, and man. I was exhausted. Oh, and all without a heal posse either, which was really difficult.
The technique involved running in, *smack*, running out so Chimera couldn't draw and hit me but once. Which BH could heal pretty quick. Over and over. Wait for a Hasten, Build Up and... uh, been a minute, something else though... to recharge, smack those, and when those were on I could go in an whittle him down until they ran out with impunity. Then back to the jumpin' around. Repeat until Chimera is toast.
So yeah. That was my greatest ever accomplishment in the game. Soloed Chimera +3 EB with Brawl. Woot or something. Heh. Although you'll just have to believe me, no video or witnesses, and I ain't doin' that again. ð
/Others did witness several Fake Nemesis GMs in Atlas that got Brawled. ð