As I mentioned in a comment on FFN, Tobias having the elephant morph was kind of a weird accident, honestly. I was writing their trip to the zoo, and obviously a lot of the key plot points here are borrowed from #01: The Invasion, but what I never noticed about that book as a kid is that while Tobias and Cassie do go to the zoo, whatever they acquire there is never used. Tobias shows up at the school in the hawk morph he acquired from the WRC, and when Cassie morphs in the Yeerk pool, she goes to the horse she acquired from her barn. Cassie was easy, I just gave her the wolf morph. Tobias was trickier. I was really considering giving him a jaguar morph, but that idea never gained any traction. It occurred to me that while Rachel morphs an elephant in the first book, after #07: The Stranger, her default battle morph is the grizzly, and she doesn't use the elephant so much after that. So I figured if I'm going to have the bear and the wolf in the fight, between a horse and an elephant, the only one I really would miss in a fight would be the elephant.
[spoiler]As far as Tobias becoming a nothlit, yes, that's still going to happen. There's really no way for me to write this series and not have Tobias trapped as a hawk. I feel that I can change a lot and still have the series work, but some things just change too much. For example, I wanted them to be older so that I could include profanity, drugs, sex, and darker tone. But on the same token, if they were, say, college students, I don't think the dynamics would work. I really think 16 is as old as I could make them and keep the series. So Tobias is definitely still bound for his hawk fate. I just decided it didn't need to be this book. In #01: The Invasion, these kids find an alien, are given the power to morph, watch that alien die, and then spend the next three years fighting a secret guerrilla war for an alien they knew for at most half an hour. I took the mindset that for Elfangor to matter that much to them, he shouldn't just be that quick of a plot element, but rather a significant character. I wanted to build him up, give him interactions with the group, and make Elfangor matter. He has to die, you're right. That's one of those things that has to happen for the series to work. So obviously his role in this book is very inflated compared to the original series. So with as much focused on Elfangor, I felt it was the wrong title for Tobias to nothlit. They're given one damn rule, and in canon, they break it in their first mission. I think it's too much to throw on the reader. My plan is actually to keep Tobias as a human for a bit. He's still going to become a hawk, but I think it works better for the narrative that he be a full member of the team for awhile. That way not only is it tragic that he becomes a hawk, but also it is a huge loss to the team that they've lost a member.[/spoiler]