Headbanger?

[SDY]

Achievement, potentially spoilers (though the in game text identifies the goal, so... not really).

I headbanged the Ritch Hive Mother as the killing blow, and I did not progress with the achievement (still reads 0/20).

Did I miss something?

[breadsmith]

Is it possible she was poisoned, bleeding or burning when you hit her? If so, any of those could have stolen the kill.

[SDY]

Phooie. Didn't see anything, but... never can tell.

One thing that's also not clear - is it 20 in a single playthrough, or 20 generally?

I built a Yeek Marauder on the terrifying idea that it was 20 in a single playthrough and that I'd have to get as many of the easy early bosses as possible. Yeek Marauder is quite possibly the worst start imaginable.

[breadsmith]

Not sure myself, but I think it's in one playthrough. And if it helps, I'm pretty sure that farportal bosses count for it.