Ok, this is seriously the best Anime series I have ever seen. I highly recommend EVERYONE in the WORLD to watch it. Its so amazing. Every aspect of the show is 10/10 (except maybe comedy) and when you realize that it was made so long ago, you appreciate it even more. The main character, Gattz, is pure 0% bullshit. He's not a goody-two-shoes... nor is he one of those characters that LOOK tough but really are a nice guy inside... this guy is coolness. Add to that his HUGE ASS sword Yes this is the original anime to feature a ridiculously large sword (as far as I know).
You know how sometimes when you're watching something... you think to yourself... 'this guy is a moron! if I were him I'd do this and that...', well this guy will do this and that... very satisfying. The music for this show is also very, very nice and touching. It goes very well with how the events unfold on screen. Since the anime is pretty old, the art isn't the best of the best, and you don't see embedded 3D graphics. But there is really no need. The action is adequately conveyed to the viewer.
The character development is amazing and detailed. The main strength of the show would have to be its story. Another plus: NO FILLER! I repeat, THERE is NO filler in this show! Pure plot development 100% of the time. Its unfortunate though, that the series wasn't completed. The story is truly excellent, but for some reason they stopped making anymore after episode 25.
Another thing to keep in mind. Chronologically speaking, the first episode comes in the end. So after watching the whole series, watch episode 1 again. It will have new meaning. What are you waiting for! Go! Watch! (but not with the family, lots of blood, and a couple of boobie scenes)
Annoying Character: Caska (only in the beginning though)
I give it a 10/10
Bottom line: "You owe yourself to watch it. "