Yo, Onur; learn to make starting messages rational. I rather doubt you did anything else than check your player list. Listing all bands you've ever listened doesn't count.
As for my favorites:
I'd start with the amazing At the Gates and Edge of Sanity; new wave of swedish death extraordinaries. Newer melodeath is worthless when compared to these two giants. Then again; I don't compare.
Finnish folk/black metal deserves a mention; it's rather original; rather inbred when it comes to members, but still fresh. Moonsorrow, Finntroll and a few others being the best.
Off we go to yankees; thunderous Nile, grandfather Slayer and nearly original Sepultura(yeah, Braz, I know). Especially Nile holds a high place among my favorite death/thrash bands. Yeah, I mix them rather often.
Other genres rock too. I like Manhattan Transfer, Chigaco Transit, Orphaned Land, APOCALYPTICA(!), ELP, The Nice, Glittertind(folk/punk). Gregorian covers, Within Temptation, Tchaikovski, Sibelius, Merikanto and a few other classic authors, some jungle and a few noise artists.