This anime is based off a browser game, and as such, having a good, working knowledge of said game will help you enjoy the anime- you'll know about the characters, the story, and pretty much make your enjoyment that much better... the problem is, though, said game is a) an internet browser card game, and b) only available in Japanese.
Yes, I know there are wikis and things that talk about the characters, but honestly, it's a 13-episode anime that you could binge in a weekday if you so wanted. It's just... even a little hint of what was going on would be appreciated, instead of just having to dig up everything on our own. It's why Pokemon was so successful in getting popular over here- because you could watch a few episodes and understand what was going on, instead of just going "Okay, who is this guy... and who are they... and why are they traveling through time?" Granted, you learn a little bit, but still, it leaves more questions than answers- I think this is aimed at the people who already have a good background in the game.
I'll give this one props on how pretty it looks- it is pretty visually appealing. But also, well... that's the only thing it has going for it. It looks good, but everything else... eh.
If you're a fan of the game, you'll get more out of it, but if you're just binging it out of boredom and wanting to try something new, well... you're not going to get all that much out of it. I mean, there's worse out there, but not all that much.