At the start, it is suggested that u go to the nexus to kill some frogzards. then u come buy some armors and weps from yulgars or the starting armor shop at battleon. When u are higher level, u can go to junkhaven with the bosses in there with tons of exp. Exp bomb has 500k hp but damage of a slime. If u kill the exp bomb u will get 33333333gold and a few mil exp