Do you think the fact that they're releasing a clip already means they won't have a trailer for Book 4?
It’s quite possible, I think a trailer should still be a necessity but I wouldn’t put it past Nick to decide they “don’t need one.” There’s also the possibility that the clip tomorrow is the trailer but I don’t see why they wouldn’t just call it a trailer then so that chance is slim.
so korra isn't going to air on nicktoons now?
According to this schedule for the upcoming week, no Korra episodes are airing at all. Book 3 was supposed to air in its entirety starting Monday at 8pm with an episode every Monday - Thursday. There was even that commercial for it on Nicktoons, so there’s a small chance it’s still happening and Nick just forgot to update their schedule but we wouldn’t put it past them to just cancel it either. They could also be waiting to air it with Book 4 when that’s done some time in December.
Daniel Dae Kim told us in 2013 that Hiroshi Sato will “be back.” Since he didn’t appear in Book 3, this confirms Asami’s father will return in Book 4.
The Final Season arrives on October 3rd.