Just acoustic guitars (albeit played agressively), often vocals, and sometimes drums.
This is pretty much the trend I've seen on YouTube videos by people who play music they call "acoustic metal." That's like an oxymoron. It's a stretch to say there's a genre of acoustic rock, but acoustic metal . . . ? What do you think?
Note that acoustic metal, as I'm using it here (and in the context of most of the usages I've seen it), is not the same as an acoustic cover of a metal song. Just thought I'd get that straight.
EDIT: I'm also not talking about bands who mix acoustic into their songs between or alongside electric guitars, just ones who use acoustic the whole time.
Distorsion dosen't have to come from electric guitars. Hell, most ritualistic bands don't play any instruments and have more of a violent Atmospheric Noise feel to it but I still consider them Metal due to the violence of the music and the slight hints of distortions here and there. Botanist is Metal without a doubt, However Qwertzuiop isn't Metal... I don't get it. I know I don't consider him Metal, I just can't put my finger on why.
I agree that Botanist is metal, that's some badass dulcimer. For Qwertzuiop, I'd say from the one song I heard by him that he's more ambient.
That's not really metal, although you're right about there being some metal- and punk-influenced aggression added.
I dunno, man. I think O'Death is a bit metal "in spirit", at least. And definitely more so than a good amount of "heavy" bands think they are. Metal reaches out to all ends of the musical landscape, in one way or another. It allows us to even consider a topic such as this. It's wonderful. ^-^
"Information is not knowledge
Knowledge is not wisdom
Wisdom is not truth
Truth is not beauty
Beauty is not love
Love is not music
Music is THE BEST..." ____Frank Zappa