I remember when WarioWare was first released, they had a site promoting it with little Flash games. They were so horrible that I completely avoided WarioWare for months before I finally broke down and played the masterpiece. I wondered what had gone wrong with the promotional games -- was it impossible to program fun, WarioWare-ish games in Flash?
Four Second Fury provides the answer. No, it is not.
If there's one thing I hate more than zombies, it's meteors. So I'll gladly accept any opportunity to destroy them, but I wish I didn't have to kill every last dot before progressing.
I'm digging the style, though.
To Oink and Rusty: Once you build a wall, you can upgrade it by clicking and holding the top part of the wall (it'll turn light gray when you mouse over it). Once the wall is 2 stories, there will be a window you can click to deploy a knight (more of an archer, really). If you don't deploy a knight, you can also choose to click and hold the top part of the tower again to build it to 3 stories. If you deploy a knight after doing this, you'll get an extra square of range.
Hope that helps. This was confusing to me at first too.