that's a very fun game, and I got the ending where you turn back to the throne (which I think is the good ending? I don't know what different endings are there), but I got a few problems as I was playing.
the first is the difficulty in activating skills, there are so many skills and buttons you need to keep track of and it's kinda distracting. would be great if there's an upgrade that lets you toggle which skill auto activate and which are manually used.
the 2nd is a bug with the 666 demons slain sound effect. for some reason it keeps repeating over and over and over again every frame and I don't know why it keeps doing it. it only stops when the boss is dead. (Speaking of the boss, the first time it spawn it seem to take 0 damage, that or my equipment isn't strong enough, but I almost bought all the upgrade at that point.)
and the 3rd is the lack of blue orb (I believe that's exp?). at the end I'm lacking a ton of blue orb to upgrade the rest of the upgrade, instead I have an abundance of coins that I don't know what else to use them for. I think the resource requirement/payout need a rebalance.