I am sorry you had such a hard time with it.
Here is a video of how upgrades should work
Both of these problems are ones I haven't seen/heard about before, but I am very sorry that you had such a bad time with my game ;_;
Yeah, that is how I thought it worked. But in my experience cards disappeared from the upgrade screen with no rhyme or reason, and upgrades seemed to only be possible when you had 3 or more of the same card, even though you only need 2 to combine.
Oh, is that what it meant? I interpreted it as buy a key to skip, not merely retry. Since that would mean making the game harder for bad players, it didn't even occur to me.
yeah, we wanted a penalty for failing and a system that rewarded replay. So keys add up so if you grind the previous level you get that many tries at the next. And if you sell cards make money you can do more retrying. This was our first game ^^;
I think the problem with upgrading you are having is that one or more of the cards you are trying to combine are still in a deck. We weren’t able to get the game to not crash when you consumed a card that was in one of your decks. So you need to make sure they aren’t currently in one of the three presets. You can see what decks they are currently in when you click on them in the library. It is at the bottom of the info/pop up.