If you like Opeth, what other bands do you like???

And let the namedropping begin.

Therion, Edge Of Sanity, Kansas, Black Sabbath, Blue Öyster Cult, Atheist, Morbid Angel, Eddie Meduza, November, Theory In Practice, Helloween, DIO, Bathory, Nifelheim, Meadows End, Nick Drake, Soho, Entombed, Nick Cave, Mostly Autumn, Thin Lizzy, Pantera, Pestilence, Blind Guardian, Tension Head, Emperor, Candlemass, Metallica, Merciless, Mercyful Fate.

Those are the bands which i have full discographys of.
 
Ahaha.. Okay.. I'm going to give you a huge list of bands that'll hopefully keep you extremely busy! Not in any order.. I'll literally rattle them from my head ahaha..

Ulver, Enslaved, Akira Yamaoka, Alcest, Amesoeurs, Neurosis, Weakling, Akercocke, Aphex Twin, Skinny Puppy, Negură Bunget, Deathspell Omega, The Axis Of Perdition, Emperor, Blut Aus Nord, Tenhi, When Day Descends, Envy, Godspeed You! Black Emperor, Genghis Tron, Thee Maldoror Kollective (T/M/K now), Aborym, Isis, Drudkh, Cult Of Luna, Primordial, Tool, Ved Buens Ende, Vehementer Nos, Fleurety, Shining (both the swedish and norwegian bands), Wolves In The Throne Room, Clad In Darkness, Winds, Arcturus, Code, Dødheimsgard (DHG now), Manes, Meshuggah, Mono, The Meads Of Asphodel, Ephel Duath, Jesu, Vanessa Van Basten, Cynic, Cryptopsy...

..And my mind is blank..
 
To add some good bands that i unfortunely lack a complete discography of.
Novembre, Lumsk, Arcturus, Isole, Spawn Of Possession, Råg I Ryggen, Grand Magus, Meshuggah, Space Eater, Himinbjorg, Bloodbath, Vintersorg, Winds, Aeon and finally Carnage.
 
Excellent Metal , for me, requires a consistent cataloque. With that in mind, Enslaved, Primordial, Katatonia, Ulver, Immortal, Negura Bunget, Wolves in the Throneroom, Novembers Doom, My Dying Bride, Agalloch, of course, Opeth and non-metal I have to give it up for, Porcupine Tree. And I forgot, The Devin Townsend Band.
 
Porcupine Tree, Radiohead, Dream Theater, Neil Young, The Mars Volta, Led Zeppelin, Muse, Cradle Of Filth, Pride an Glory, Anathema, Dillinger Escape Plan, Greenday, Martyr