I died once because I turned my back to her adds I wasn't aware showed up and they bopped me. My 2nd attempt I flawless victoried those hoes.
I did, and I took down BSB in one try and have spend way less time on a few objectively harder bosses. It's not a particularly hard battle, but I just kept getting caught in that one witch's grapple beam and then she'd slit my throat and before I could heal I'd get hit by a minion.
I didn't even beat them for real. The boss battle that I won on had some bug when I got the first witch down to a sliver of her health. The health bar didn't go down but she still died. Then the second one appeared but had the health bar of the first witch (with only a sliver left) so I hit her once and she died.