I beat the game, took a lot of tries. the two behind town are the hardest to kill. Especially the one in the middle, go for the left one. Then the one on the other side of town from burts then the one in the back corner. The one in the middle behind town is really hard to kill. couple tricks, run right at the graboid and jump right before he gets to you then run in a around them. takes a lot of practice but i have beaten the game two times. There are FIVE graboids but you only need to kill four to win.