What are you listening to right now?

Does Slayer have a more brutal album?

Probably not, it's not death metal after all. And for thrash, they're quite heavy.
Actually, if you want good thrash, listen to Megadeth. Although they don't sound like Slayer, and some even say they're not really thrash.

Spirit of Sorrow - Silence's fortification

Not bad atmospheric black metal, worth a listen, although the vocals are a bit grating.