Glitch!
It happened three times in a row. First time, i lost, game stuck, did not advance to you lose screen. Second and third time i beat the computer and it did not say i won, just stayed in the game with computer's castle gone.
My guess on why they removed your game is because the theme is endurance, and this game does not involve enduring. You just leave the game alone. I suppose you needed to have a goal which involved lasting as long as possible by doing something to endure.
Too slow paced for me. Got to level 21 and it was still slow. At first i thought the AI would improve over time, but that didn't happen. I also thought more enemies would enter the arena at once, it happened, but without improved AI, or at least speed or quicker fire rate, i killed them all too easily.
Great game. One of the best flash fighting games, and it doesn't lag. If you people check his site, you can find out why he can't finish it. So check his site ;)