I would like to know what each upgrade do like in percent, values or something, I have spent 100$ on reward upgrade expecting reward would go from 5 to 10, but it only got to 6 :/
I'm pretty sure that empty waves issue comes from encounter rate, when I had 5ER, I had 1 monster every 5 waves, now when i have 20ER I get 1 or 2 monsters every wave
This game is a very good proof of concept, you have the basics but it have no real content, after a few hours you're done, there's nothing interesting past lvl 1.100, idle games should last months, this one doesn't. You should add much much more content, maybe recursively tougher blocks, for example: start with all white blocks, then some of them are yellow, when you have full yellows then blue, etc, black should appear around lvl 100K or something, maybe special blocks that are immune to certain ball, maybe random gold blocks in normal levels etc. Overall very solid start, but content is non existent. You can get a few ideas from Time Clickers. Good luck.
At first it looks like Idle Ants, but you'll notice quite fast, that the mechanic is totally different, it's not copy-paste with different names, definatly worth playing!
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 "Basic Run TD"){kind=icon}
 "Idle Labels Puzzle"){kind=icon}
 "witchy sacrifices"){kind=icon}
 "Collision Idle"){kind=icon}
 "OnTheWay"){kind=icon}
 "Incremental Popping 2"){kind=icon}
 "Defender Idle 2"){kind=icon}
 "Idle Breakout"){kind=icon}
 "Monster Clicker: Idle Halloween Adventure"){kind=icon}
 "Universe Builder"){kind=icon}
 "Idle Medieval"){kind=icon}
 "Reaper of the Undead"){kind=icon}
 "Castle Woodwarf"){kind=icon}
 "94% Online"){kind=icon}
 "Clicker Fred"){kind=icon}
 "Heart of Galaxy Beta"){kind=icon}
 "Upgrade Complete 3"){kind=icon}
 "Zenge: Starborn"){kind=icon}
If I make an update to the game, I'll add a setting to change it.