You can beat the game indefinitely by abusing the Vampire. I got to Cheater? mode (beating the game 8 times) by increasing my intelligence to at least 802. How the Vampire works is that you take significantly more damage while at lower amounts of SP. However, the converse is true. At 501 SP, you will have permanent 100% damage reduction. Without abusing this bug, it would be incredibly difficult to travel past Stage 60+ because every monster deals about 500k damage (damage scales much faster than you can put in Vitality late game)
After you get 802 Intelligence, just dump all your points into Dexterity and use the Frozen Set. As the game progresses, you have to watch out that you don't start dealing too much damage. What happens is that the health you heal per attack will overflow the game, causing you to instadie.
Rofl. You know what I do. Between levels first I plant all of my 60 barrels, then call an airstrike for some uber explosions. Wasteful but you get to see fireworks!
 "Loot Heroes"){kind=icon}
 "Boxhead: The Zombie Wars"){kind=icon}