Anime/Manga Can you identify this anime?

A couple days ago I randomly remembered an anime I watched for a short time years ago, originally either on Cartoon Network (probably Toonami) or Adult Swim. I can't remember the name of it though to look it up. I don't remember much about it and I remember kind of getting bored of it, but I'm not sure if it's because it wasn't that good or if I just couldn't really appreciate it at the time.

From what I do remember, I think that the main characters ended up travelling to another world. I think there were two main characters, both male, and they ended up going to the other world at slightly different times, so I think they were apart from each other for a while. I vaguely remember something like little gems/spheres being used to upgrade weapons or something and I think there was some sort of tournament? There were flowers that glowed in moonlight and a female character who I think was a princess who at some point wished she could be reborn as a bird so she could fly away.

As I'm describing it, it sounds a lot like another anime called MAR, but I know that's not it. It had a more serious tone to it and a less cartoon-y art style.

If anyone ever manages to tell me what anime this is, I guess I'll use this thread as a discussion thread about it after the fact.

 

Action? Adventure? Fantasy? Something along those lines.

Edit: pretty sure it's not Ragnarok, but that looks interesting.

Edit again: It's Kiba! @Junkrat mentioned it last night on Discord. So I guess I'll watch it now and see how well I actually remembered the few details I was able to remember. I think I already got something wrong. I vaguely remembered a character putting the shards (the spherical gem things I mentioned before) into his arm or leg or something, but I also thought I vaguely remembered them being added to a sword. I thought adding them to a weapon sounded more likely so that's what I went with. Who knows, it might be both. I really don't know!

So has anyone else seen this anime before? What did you think about it?