Heavy pay to win features in this one. You get next to nothing for 12 hours of idle rewards, but you can't progress through stages without more resources from being idle, so you'll be stuck waiting for days to make even a little progress. Summon currency is very limited. The tower needs adjustment as lower CP teams will obliterate your higher CP team. If you spend money, you obviously won't have these issues. The art is excellent, though, so I guess they need to pay their artists somehow...