Aang will master the avatar state like he almost did in the last episode, Sokkas father will get killed, and Aang finds airbenders that have been hiding out for 100 years. Aang and katar also have their first kiss. Thats all i got but there are rumors that Aang takes power as fire lord once he defeats him and another season will come out that Aang is overthrown by Azula and he has to fight for power again.