Good fun!
Played on Easy till reaching 6.553 billion before getting bored and letting all balls run out, which is still happening and taking awhile.
I've never seen so forgiving a pinball game; it's practically impossible to game over if you actually care what's happening on screen. The variance in mobs/targets is good, the dungeons are GREAT little instances of fun, and are fairly difficult (mostly because, esp in the 2nd one, so much stuff gets hit it's difficult to keep track of where your ball ended up). Then there are fun little mechanics like the bell you can try to hit, the 12 zodiac signs up top, the octo-like mobs that spawn up there (esp the large one that can die, but takes quite a bit of punishment), etc etc. It can take awhile to find all the cool little niches the game holds, really awesome =)
My only real issues are:
A) I don't think a dungeon should be difficult because you can't see what you're doing, it encourages weird playstyles that include NOT hitting things which is backwards thinking. Maybe tone down the visuals upon hitting/killing a maggot or zombie.
B) The 2nd dungeon is great, but when it gets down to the last 1-2 graves, hitting them can be really difficult without others to bounce off of - and is it just me, or do their hitboxes get smaller the more damage they take? I guess that's just logic, but it does increase the difficulty a bit, make sure you intended that to be the case.
C) In the Skull boss dungeon, I can see how the portals on the left/right are supposed to add difficulty by confusing you, but the ball always comes out on such a low&slow upwards trajectory, it gives a LOT of time for you to look over defeating its purpose, and if a zombie doesn't happen to wander by when it comes out, it takes so long for it to come back down to the flipper, you're guaranteed to lose your combo. So once I'd beaten it, I went back to dungeon 2 for score purposes.
Lastly D), once the smaller octo's and Green arrows showed up in the main map, getting into the first dungeon (the lower one with the pyramids) became practically impossible without getting shot back up into the middle or upper sections, so my only option was to sit back with my hands in my lap, perhaps for over a minute, waiting for it to fall back down.
Either way, good fun, and I wouldn't be surprised if a lot of my noted issues are solved in higher difficulties - I just don't have the patience to find out. Cheers!