ummm....i'm pretty sure there is no solo in that song....unless you're talking about the 2nd heavy riff (yes, that's my favorite Opeth riff, by the way)
The great instrumental "Epilogue" is like one big solo. Some people think that they're lazy solos, but I actually think they're quite inspired. And it's one of the few songs that hits me the same way it did when I first heard it.
But if that doesn't count, then I would say the outro solo to "The Twilight Is My Robe." It's short and hits you hard.
you're right, that solo is badass.. i would love to see that song live so much, its one of my favorites.... so fucking epic, i want to mount a steed and just slay people in some glade...