I've never liked the sludge metal that was all about making tons of noise and having some guy who's screaming his lungs out. I like the sludge that has the lazy, Black Sabbathesque take on music and either refrains from using vocals too much or has a guy in the front who can sing or, alternatively, growls. Ocean Chief from Sweden stay with in the bounds of what I like. The first time I listened to the first minutes of the ten-minute album opener, the title track Universum Härd, I thought this was a Triptykon clone band! Yes, it's that heavy. So, be warned; you have to be in the mood for something that at times is slow and dragging and makes you want to just sit back and contemplate the misery of this mortail coil. Luckily, it's not just 42 minutes of that, though.
The tempo does vary throughout, and there's a bit of melody here and there, even! Three tunes are instrumental and the Swedes use these opportunities to explore the borders of the genres they embrace, and they do so excellently.
If you're looking for something heavy, something slightly noisy, yet something which gives you room for contemplation and swimming away, try Ocean Chief.
Here's a link to an album teaser on youtube if you dare: