This doesn't smell like mushrooms to me. It smells better than mushrooms.
To me, Deathcap has three sort of "layers" to it. The first is dark, moist, mineral rich dirt (maybe with a little bit of iron in it, a little chalky). The second is sweet, oily coconut husk, and the third is something white and nectary - like standing downwind from a distant honeysuckle bush. The effect is like the smell of a glazed donut dropped on a shady patch of turned earth. It sounds like an odd combination, but it really works.
This is my favorite of all the Bpal oils I've tried (I just started, so I've tried less than 40, mind you) and I wear it the most often. Usually to work because I find it cool and relaxing. I work in a stuffy room with no windows, so it lets me pretend I'm at least getting a little fresh air.
I also have problems with getting headaches from perfumes sometimes, but this is so mild and soothing I feel like I could roll in it and wear as much as I wanted and never get a headache (not that I do, I dab and can still smell it on myself very well. It wafts, and on my collar bones it lasts all day long. When it does dry down it's to a sweet and pleasant powdery smell). It's a great sort of neutral scent for me. I'm kind of paranoid that it will be discontinued randomly while I'm not looking, and if that happened I would cry - so I should clearly buy several backup bottles just in case.
