Might I suggest people who enjoyed this game check out Teeny Titans? It has superheroes, Active Turn Battle systems, collection, leveling, gear and tons of charm. A bit on the easy side, but much more accessible. And as a premium game, you buy it and get your money's worth for sure.
Request your refunds if you bought any IAP! Apple is being quite responsive on this one, especially since customer service reps were telling people that it was in no danger of shutting down and referencing new content... content that arrived with the shutdown notice. It's fairly obvious it was to keep people on the hook until the last possible moment.
Not necessarily, it's entirely possible that the development didn't get informed about this being shut down, from the higher-ups, until after such content was released. Thus, not knowing this was gonna happen, until it was too late. This wouldn't surprise me one bit. Disney seems to want nothing to do with video game stuff, as of late.