what about an rp based on Underworld. You know, the movie where vampires face off against werewolves (here called Lycans) in a modern-day "war of the species"? Here's a preview:
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The war had all but ground to a halt in the blink of an eye. Lucian, the most feared and ruthless leader ever to rule the Lycan clan, had finally been killed. The Lycan horde scattered to the wind in a single evening of flame and retribution. Victory, it seemed, was in our grasp, the very birthright of the vampires. Nearly six centuries had passed since that night, yet the ancient feud proved unwilling to follow Lucian to the grave. Though Lycans were fewer in number, the war itself had become more perilous, for the moon no longer held her sway. Older, more powerful Lycans, were now able to change at will. The weapons had evolved, but our orders remained the same: Hunt them down and kill them off, one by one. A most successful campaign. Perhaps too successful. For those like me, a Death Dealer, this signaled the end of an era. Like the weapons of the previous century, we, too, would become obsolete. Pity, because I lived for it.
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we could split the sides into vampires and lycans... then work the story along from there.