Help!!PSP Chilli Con Carnage!?

Im bloody addicted to chilli con carnage for the past 2days and cant get past the level 10 (i think),its called arena del toro..What do u have to do to get past it?The objective says that u have to kill Morales' bulls,but it just doesnt seem to end!The damn bulls just dont stop coming and keep dying.Is there something im missing?I know theres some 14yr old comp. addict who knows the answer to this one!Thanx xx