(hey, look who's been sucked back into the Warriors fandom)
What if the clans never left the forest? What if the forest was never destroyed in the first place....
It has been centuries since Firestar was leader of thunderclan, and the four clans, Thunder, Shadow, River and Wind, are still flourishing in the forest. It has been rather peaceful for many moons, though tension is starting to build up and a few rumours have been spreading saying that the Darkforest will return, as well as claims of a deadly clan of rouges who live in a massive abandoned twolegs den and are not particularly fond of the clans.
So this is where your story begins, and may Starclan light your path.