It was said that the King fell from grace so abruptly that the earth opened up beneath his citadel so he could fall for eternity. This is exactly what happened...
Down it falls, a great concentric castle of dark stone. Cracked and broken, though upright, pieces large and small fall together in concert, frequently dashing against each other, or drawing apart to create wide gulfs to expose the hungry blackness below.
And in this tumbling castle, there sits a king, his head heavy with his crown, his hands clutching his throne in unending terror.
The fort seemed like every small boys dream, but in fact it was a very well made magical prison, and the young prince only learned the truth when it was too late and the magic sucked him inside, his cries from his now inch high body too quiet to be heard.
The PCs find a strange helmet, when donned it will take control of that PC and speak and act trough him/her. It explains that it is benevolent and needs their help in a quest and that it will stop possessing the PC when the task is done. Great if a player is gone for a number of sessions.