Boxes. I fucking hate those boxes. They can easily turn what could be an amazing run with a horde of about 30 zombies into an impassible blockade that whittles your horde down to nothing in less than a second. Yeah, you can tell this is designed to be a mobile game because half of the time, when you're too focused on destroying boxes ahead of you, you're often missing brains that fall down behind you to increase your dwindling horde; you can have a thumb on either side to mop up the mess, but you only have one mouse. Those boxes are the only reason that it took me so long to even get the 1000-meter running medal, because more often than not, I'll miss them among the crowds and crowds of humans shooting at me or running past... and it only gets even more obnoxious when the crates turn into brick palettes.
Another thing that annoys me is the rampage. Not just the child's voice that overpowers every other sound in the game, you don't know how long the duration lasts. Don't get me wrong, I love not being able to click on boxes for a whole three seconds, it's that it never feels consistent. Half of the time, it feels like it never really goes off at all, and again my zombies will get stuck on a single box that ends up getting them all killed. You probably could've eliminated both the problem of missing brains and obnoxious obstacles by:
- having a duration meter for rampage mode somewhere, or having the button you press to activate your rampage BE your timer;
- creating a new upgrade option that lets you increase the duration of rampage ever so slightly; and/or
- creating yet another upgrade option that gives your zombies an X% chance to create two zombies with one kill, maybe incrementing by no more than 5% with each level.
This is not a game that was designed to be Flash-friendly. Instead of a small sentence in the third paragraph of your game's description, maybe a brief disclaimer at the start of your game would help disperse some of the hate you're getting and have more comments referring to actual bugs and glitches within the game instead of fundamental problems that make it frustratingly difficult to play. Maybe then, you'd be getting fewer zero- and one-star reviews like mine.