Most difficult Opeth songs on the guitar?

Alexis Laiho and his stupid rebel sex drugs and rock n roll attitude are just ridiculous and.. ridiculous. I have no respect for the new direction the band has taken and I don't think he used his talent wisely.

Well, also he looks like a wannabe teenage goth girl but hey, he is technically advanced. (well I just remembered how I hate his image lol)
 
I think SPD or Face of Melinda are pretty damn difficult to play.

A kind of on topic question for the guitarists out there:
Most musicians follow some kind of scale pattern when writing music (like how most classic rock follows blues scales). Does anyone here know or have a guess if Mike follows some kind of scales when he writes music? His writing is so genius, though I do have a hard time believing sometimes that his stuff comes out so well simply because it just "sounds good". I also assume that learning and getting used to the majority of the scales used would make learning the songs easier...
 
I think Mike said whether we believe it or not that he doesn't know much music theory - at least until Watershed, I think in a talking metal interview he said Fredrik taught him some when they were hanging out - and that he basically writes down whatever sounds cool. I'm sure that's a slight exaggeration and he knows some basic pentatonic scales and open chords but...ya according to that there might not be a specific style.