Below are some perennial favorites.
Agalloch - Folk metal, heavily layered and focused on the beauty of nature. I visualize harsh tundra, deep forests, and majestic mountains from their music. Both The Mantle and Pale Folklore are killer albums. Sample song (two parts):
Bathory - Viking metal, extremely atmospheric, chugging guitars. The pacing builds up to these instrumental and vocal crescendos that send you like a flaming arrow into the skull of a fleeing peasant, Norse warriors hacking limbs and torching homes in the background. I recommend Hammerheart. Sample song:
Blind Guardian - Power metal as it should be, with a vocalist that doesn't sound castrated. Nightfall In Middle-Earth is the most epic album that I've ever had the pleasure of experiencing. Soaring choruses, smoldering electric guitarwork, and emotionally charged lead vocals. Sample song:
Mastodon - Raw, paranoid, and utterly captivating. Crushing bass, blistering guitars, aggressive vocals. Leviathan is their masterpiece. Sample song:
Other recommendations:
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