Hmm, it's really pretty... but it also looks really bare. :/
Here's a few aesthetic things:
- The art probably should pop out a bit more. A few ways to do this would be cut off all art from going beyond the bars, namely Giratina's tentacles (at the top) and Palkia's wings (at the right)
- The art fades out really suddenly. I think you might have feather it, where the fade should be really gradual. I'd suggest using a black-white gradient and a clipping mask and/or large, low-opacity brush. The other option is to do something like the Palkia & Dialga LEGEND art, which would look even better if you can pull it off.
- The art probably should be a bit more contrasted. There appears to be shadows on Dialga which looks a bit odd; not sure if you can do much about that.
- The edge of Palkia's wing looks a bit like plastic - it looks like Palkia is separate piece of art (it probably is, but you may like to do some manipulation on that).
- At the rightmost card, the bar can be seen through the pink/purple clouds, which is a bit odd.
- You may like to make the name and LEGEND symbol a bit more gold-y.
- There really need to be more text. Try to aim at 6 attacks, with two on each card. Wordings attacks work well too.
- The attack text effect looks too large in contrast with the other text on the card; compare to official LEGEND cards. The attack names look fine, however.
- The attack text goes any-which-way, where it should actually follow the art a bit more and should be in a smoother line. Things like "of", "80", "20+" and the Energy symbols look really wonky; compared to official LEGEND cards.
Mechanically, it would make sense for the LEGEND rule to be "3 prizes" not "2 prizes", but I'm not sure if Asche has already set that.