This is one hell of a ferocious game which requires timing, and a little bit of skill and knowledge.
The trick is to set up a maze that will take the creeps longer to get to the opening on the other side. But on the way you will encounter many different types of creeps, such as fast, group, decoy, dark, morph, immune, and several others.
There are also different versions to the game, but my personal favorite is the 1.2. There are also different modes you can play in that may sound hard, but are actually quite fun.
Enjoy!
