So I commented back in May that this game is literally unplayable for me, because as soon as I start a battle, it immediately ends in defeat. Well, today I poked around the interface a bit, and I've figured out what's going on. Looking at my deck, I see that it has... 0 cards. Apparently, the very first time I launched this game, it gave me a starting deck that is completely empty. So I have no cards in my deck. And no cards outside my deck, to add to my deck. And I assume the only way to obtain more cards is to win them by completing battles, which requires you to have cards. Which I don't have. And there doesn't seem to be an option to delete the save game so that I can start over from scratch with a proper starting deck. It apparently glitched in such a way that I will never be able to play this game.
This game is literally unplayable. I get "Challenger Approaching", followed immediately by a Defeat screen, with no opportunity to play any sort of game.
Level 25 is nearly impossible, because it causes the game to max out my CPU, and then the slider controls become almost completely unresponsive. I had to quit and restart my browser several times, and even tried on 2 different computers, before I managed to push through to completion.