War of the Roses as a campaign plot. Two noble lines converge somehow, each line thinks it has the rightful claim to the throne. Deciding this long ago was handled by some divine intervention, requiring both houses to come together at some point. They aren't so willing to get together this time. Civil war, or a new king?
Shadows, Mirrors and Flames. Three things we have all seen and not given much thought to. What if in each of these things you could find entire alternate planes of existance? Shadows move but what they are shadowing does not. Mirrors show us what others can easily see. Flames dance and twirl inviting you to dance only to scorch you when you get close. These three things hold much mystery. What if you could harness their powers? Heh...