I found what appears to be a fun bug in the game. Once I purchased the fifth upgrade for my speed, the 400 diamond one, it gave me the option for an 800 diamond update. I grinded a bit, got enough for that and when I clicked it, it upgraded, but didn't subtract the money. I hit the button a bunch of times, got the score high enough that it reset the counter and began subtracting small amounts of diamonds from my total. Now my shots are super fast and have giant, bright colored explosions on them.
Anyone else run into the bug if you click really, really fast on the buy button for valve flow you end up with a negative balance?
http://i.imgur.com/hepoL.jpg
I'm experiencing the same glitch on level one and two that has been mentioned a few times now, where you fall through the floor and appear up high. Every time it happened, i was at the far right. Also noticed on the boss fight, if you can jump high enough to get most of the wave off the screen, all waves disappear. Other than that, fun little game
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