There's a movie out there, on premium movie channels mind you, called
Freaks of Nature about a town of humans and horror movie style monsters fighting off an alien invasion. Though it's not very good from what I've heard. As for genre mash-ups, God that's a tough one. For one I like fantasy, mid to high power fantasy to be exact. With characters ranging from skilled neophytes all the way to epic heroes like the greatest of those from myth and legend, their world's mightiest heroes. They plum the depths of the Underworld and shake the pillars of Heaven, then steal everything that isn't nailed down. These heroes, whether bold warriors, potent magicians, cunning and nimble tricksters, gifted orators or mediators, intrepid scouts or masterful polymaths, often travel to strange new lands. There they see exotic and breathtaking cities, gaze upon beautiful landscapes, uncover lore and artifacts from the past, battle foul and oftentimes unearthly foes and meet new and interesting people and creatures, and sometimes kill them.
As for other genres to mash up with fantasy, you have action and adventure, which I tend to fold in with fantasy anyway. You also have horror, supernatural and otherwise, crime/mystery, comedy, spy thriller and more. If you want fantasy James Bond, be my guest. Or if you're more of a John LaCarre fan mixing it with fantasy can also work. You want swashbuckling adventure on the seven seas with demi-god like heroes and dreadfully powerful sorcerers, perfect. You say that some of ships can fly as well as sail on the ocean, even better.
The PCs are young adults being stalked by supernatural killers, or plain masked maniacs, attempting to murder them for perceived sins committed by them or others like them. Boilerplate slasher flick plot. They're actually all working together to survive and vanquish said threat? Sounds promising. They all have specialized skills and training, possibly even supernatural powers? Now you're getting somewhere. Dear slasher, you are now on the verge of ceasing to be the hunter, prepare to become the hunted.
That's all I have for now. I was about to go on a tangent about a fantasy
Pulp Fiction or
The Big Lebowski, but I really don't feel like going into that much detail right now.
