Indeed! Any particular way you want this to go in terms of specific plot-points or is it a free-for-all going in the general direction of the plot?
And how bout for the extra characters that aren't in the Valley? Like Sierra and Rinkus, Ozzy and Strut, Bron and Shorty, and Doc? Do they have anything specific in mind in contributing to the plot or are they just free to do as they please? Did any of these questions make sense? 
The majority of the plot is actually free, just some major points are set in stone, basically. Here's the main events that must happen:
> Sharptooth finds Redclaw, they team up. (In this role-play, they're brothers)
> They decide to use Chomper as a way into the valley, they send Screech and Thud to bring him to them alive.
> They force him to tell them, he (very unwillingly) tells them a secret entrance.
> He manages to escape, and warns them, but the leaf-eaters exile him for betrayal.
> They invade the Great Valley, followed by many other sharpteeth.
> They occupy it for years, and Littlefoot is thought to be killed but escapes, Doc finds and raises him, and they soon meet up with Bron and his herd, who were searching for Littlefoot.
> Chomper and Littlefoot meet eachother a second time, so they go to save the Great Valley together, and lead the flatteeth in a battle against the sharpteeth.
> Then a big battle occurs between Chomper, Littlefoot, Bron, Cera, Spike, and Shorty against Sharptooth and Redclaw.
Other then this, the rest is up to you, and also completely new scenes are welcomed.
And Sierra, Rinkus, Ozzy and Strut are in there so people can add them if they want, but they don't have to actually be in the story, and Pterano is allowed back in the valley in this Role-play
