Pretty much that, is there an AP where a villainous Dragon is the main antagonist of the story?
I know that Dragons do appear as villains and enemies in some of the APs. But is there one where the Dragon is the actual "Big Bad" at the end of the story, and not just a pawn of the actual villain?
|The Mad Comrade|
|the nerve-eater of Zur-en-Aarh|
If you count pre-Pathfinder Paizo APs, Age of Worms has a ton of dragon enemies including one who gets by far the most build-up and time of the villains and is effectively the #2 by plot significance but the #1 for memorable.
There will hopefully also eventually be Rage of Wyrms.
Edit: one day I will remember how to use BBCode right first time.