Consider the Spinosaurus, eats a lot of fish, is bigger than a full grown T-Rex would be. Also, we can assume there might be some big mammals. Also, it says that he is, while not starving, could weigh more. He knows this but is doing it out of respect for Littlefoot and the Gang of Five and Ruby, particularly Litltefoot, who went after him at the end of film V.
We must assume that there are other creatures other than Flat Teeth, Sharpteeth, Bothteeth, Egg Stealers, small mammals, and fish in LBT world, even if they aren't shown.
I also, if you noticed, have set Ruby up for a possible moral dilemma, as if Gallim's New World Order works out, she could at last be in charge, which, as she feels underappreciated, would prove tempting, perhaps, to join Gallim and turn on her friends.
I admit I find I'm much better at writing novels and short stories than movies. (Also, I'll admit, my song making, with rhymes, could be much better, but I do the best I can.)
Also, I wonder if anything I've hinted at should be obvious to any dinos not in league with Gallim: that while Egg Stealers, Sharpteeth, and Flateeth are all falling prey to his sneak attacks, that omnivores are unscathed.
(Eventually, Chomper
is going to figure this out, but can it be surmised that he could be the first and that nobody would see it sooner, particularly someone nice like Ruby who might also see the pattern? (She actually does mention it, but doesn't put two and two together here.)
I admit, the title "Terror of the Mysterious Beyond" implies that Gallim has been to the Great Valley, which, when I first came up with the term, never occurred to me. However, he could have been there before years ago.
Gallim's kind might not be anywhere near the Great Valley (he can run really fast, faster than Ruby or Yellow Bellies) so nobody would know he's an omnivore.
Also, let's face it, if Chomper eats Leaf Eaters currently, killing them too, he can't show his face near the Great Valley ever again.
I also admit, there are movies and stuff for films 14, 15, and 16 i plan to do too to develop the Gang of Five more. I have some work on film 14 done already, a basic idea for film 15, somewhat of an idea for film 16, though less than 15, as I don't even know what types my villains would be, other than that I want a longneck villain.
I'm also trying to make it closer to actual LBT. I could easily have Chomper secretly have given into the Sharptooth side, be whacking Leaf Eaters for food but not telling Ruby, and eventually the Gang of Five would find out, and then he'd have to do some huge act of redemption to get back in their favor, but then the plausiblity of him ever being back in the Great Valley or being in contact with the Gang of Five is now thrown into doubt. It's a tricky situation either way.
Personally one of the things that I disliked about The Fox and the Hound is that, though Tod and Copper are friends forever, it appears that they will NEVER be able to meet again without putting Tod in danger. I
don't want that for Chomper and Littlefoot.
In the actual movie, once I get all the parts together, I actually intend to show the screen view from Gallim's POV so nobody can see him and tie him to the villain till he is revealed later. Gallim is actually going to be a Prince Hans type of villain (in fact, I thought of having the voice of Hans voice Gallim). (Ideally, I'd have had Tony Jay, the voice of my favorite Disney villain Claude Frollo, but sadly Mr. Jay is no longer with us.)
Also, you can see that Chomper
has considered eating Leaf Eaters. If Littlefoot and the Gang of Five and Ruby were to turn on him or dislike him, he might be really pushed that direction. You can tell he's ticked that Leaf Eaters don't even want to go near him just cause he's a Sharptooth and he feels betrayed. Also, if some Sharpteeth start liking him in addition to the Gang of Five turning on him, he'd be really in a bind.
Also, consider what it would do to Litltefoot if he were to find out that his attempts to change Chomper from that path have failed and Leaf Eaters died when he could have smashed the egg or let Chomper die in the Sinking Sand. You do realize what that would do to him, particularly as he already lost his mother and you can see that hurt him so much that he isn't celebrating his Star Day. Also, consider all the times Littlefoot has defended Chomper from Cera and the others. Do you realize how much it would pain Littlefoot to find out that, after all he did to stand up for Chomper, Cera had been right????
(BTW, I'm not saying I don't want the plot to go that way. In fact, it is going to head that way in some way, but this isn't the time for it so soon.

Chomper has already established that he has been less than honest as he never told them he
did try and hunt them in film V and also that he
has eaten Flatteth before when they last met (the reason for that is the same reason that younger Littlefoot eventually ate foods he didn't like, he got hungry enough, I mean, pretty hungry. The same thing happened with Chomper and meat. Chomper isn't afraid to hunt mammals, just Leaf Eaters and Omnivores. As for hunting Sharpteeth, a more veteran or larger hunter could do it, but he's only just come of age. He'd be risking quite a bit to hunt a Fast Biter. One would have to hunt a Leaf Eater first (not that they can't fight back) but you usually don't just attack a Fast Biter, you usually have to deal with a pack if you go for one. I had thought about adding the Chomper's parents weren't allowed to join Sharptooth communities because of their son's odd behavior (even between Films II and V, he only eats Leaf Eater meat as he kept being fed it. He is still friendly with Flatteth then too. I should add that. It would show what his choices are costing him and how easy it would be for him to turn on his Leaf Eater friends, if only to end the suffering he has to go through for it.
Chomper even feels that he is giving up having a family for his decision to not hunt Flatteth and he is willing to do it, though he is very sad about it
And, again, what thanks does he get from Flatteeth for making all these sacrifices: Mostly they avoid him and have shouted their hate at him just cause he's Sharptooth.
He has practically NO Sharptooth friends and now Andromeda, who appears to be caring, as she risked her neck to help Chomper and he feels strange (in a romantic way) around her yet he has got to be thinking "As soon as I tell her about my Leaf Eater friends, she's going to dump me."
Also, considering that if all the other Sharpteeth are hunting Flat Teeth, then Chomper, by going after other stuff, has less to compete with to get it and can get more of it. He seems fitted to live alone or with Ruby for the rest of his life. Unlike many Sharpteeth, he doesn't have to share with a pack. (Though if he joins the Sharptooth pack, he may have to turn on Flatteeth as he would stick out like a sore thumb and be banished from there for his odd behavior or whatnot.
Also, Chomper has stepped into a hornent's nest of another sort. Sharptooth packs are won one of four ways.
1.) A dominant male takes over, killing his rival and any who stand in his way.
2.) Inherit it from father who is pack leader.
3.) If the child of the pack leader is a daughter, marry daughter and get it through marriage. (Note, Andromeda is a pack leader's daughter so Chomper might stand something to gain if he marries her.)
4.) If the daughter doesn't marry, usually some male will take the leadership from her family, barring that she would hold it by force like Queen Elisabeth or whatnot (which doesn't happen often, but could happen.)
Chomper seems likely to lead the pack in the story below due to 3. While Chomper would certainly make a loving mate, there are others who'd like to wed Andromeda, not because they want to be a good mate to her, but because they might want her father's role as leader.
The pack leader already gives a good deal of power to his son-in-law upon marrying a daughter and eventually the leadership role itself upon his death or resignment. (You can, I guess, step down. Should have mentioned it in the list above.) Some others might want that and want Chomper out of the way, especially if they view him as a weirdo who they feel doesn't deserve it.
Littlefoot, on the other hand, has a problem of his own. He is the last of his herd and, I guess, though this is kinda ruined by Topsy having Tria while a grandfather, that Grandpa and Grandma Longneck cannot have kids anymore and that Bron, being single, is also unable to have more kids, that can still procreate. Hence, Littlefoot is the last hope of his old herd and needs to find a mate.
First, he is like "I'll never marry. I don't need a girl.", but later, after seeing all of his friends in love, is regretful that he's the only Longneck of his age in the Great Valley.
Then Ali comes and Littlefoot has hope of continuing his herd. However, he too has a complication: Rhett and all the time he's spent with Ali that Littlefoot didn't have and how he's going to win her heart.
It will be especially interesting when Chomper and Andromeda cross paths with Littlefoot and Ali and see how things go.
And, let's not forget Gallim and what he might do to keep the Gang of Five, Ruby, and Chomper apart as their friendship doesn't bode well for his plans.
I've only gotten started on this story, trust me.

PS, while Chomper is not skin and bones, he could definitely use a lot of fattening up. He does come to eat other dinosaurs, but luckily he finds some nice substitutes for Flatteth.
