I'm quoting from the thread about which character's should or should not return:
She [Dill] was so mean.
That bird [Ichty] tried to cut off Ali's head for crying out loud!
They [Rinkus and Sierra] were really mean and they'd do anything to take over the world.
I'm wondering if "being mean" is so much of a drawback for the declared villain of a story. If villains are too friendly (or stupid) this kind of takes the bite of a story (which is why a really stupid villain often comes along with a smarter, dominating counterpart). If all mean characters were barred from the land before time, there would be less possibilities for a good story I'm afraid. In my opinion meanness is nothing to be demoted but promoted as far villain characters are concerned.
There are two types of villains though we haven't had yet (or at least not in their worst form). One would be somebody who abuses his or her authority in such a way as to harrass those submitted to that authority. A very good example for that kind of character would be Dolores Umbridge from Harry Potter 5 (having not seen the movie but only read the book I can say that in the latter she is really the kind of character you can really hate (and love to hate; as in cheering whatever misery may befall her and approving whatever torture the "good" characters may have in store for her).
Another brand of villain character (it may overlap with the one mentioned before) is a diehard racist. And if I say racist I don't mean something like Cera's Dad's prohibiting Cera to play with Littlefoot, or Pterano's braggeries about flyers (mentioned by Petrie in the beginning of LBT 7). I mean something beyond being overly convinced of the qualities of the own kind. The worst kind of racist would not just try to establish the own kind as superior but try to get rid of other kinds (for example in the Great Valley). This is a very hot iron of course and with the increasing tendency to make the LBT movies very easy to chew for the youngest audience I do not think we are going to see this in a movie. The really bad racist is a type of villain I'm trying to work with in a land before time story I haven't yet finished to write (more than 240 pages so far though). It is tricky, but I think possible, to keep the balance between that degree of villainy and maintaining the land before time as we know it from the movies.
Finally (and once again there is the possibility of this type of villain overlapping with those mentioned earlier) we have yet to see a really good and deceitful "traitor". There was the basic idea with Pterano, but in his case it didn't really work out. Excepting Petrie and his sibilings (who didn't play a role) everyone in the story could tell that something was wrong with him and so could the audience. Moreover we still don't know for sure if in fact he was a real villain at all or just somebody who was blinded by the wrong aims and a readiness to use many (not whatever) means to achieve those. We haven't yet had a villain we couldn't recognize as such within a few seconds from his or her appearance (speaking of his or her, Dill was the only female villain we have had so far). It would be cool to have a villain who fools not just all or most of the characters but also the audience for a while. Someone who comes across as honest, kind, noble, and trustworthy and then turns out to be a villain when you and the characters least expect it.
