The hc_bingo April challenge is for a crossover (meep!), using at least one of the prompts. My prompts this year are:
|serial killers||asphyxiation||falsely imprisoned||accept injury to protect someone|
Nope, I've got no idea what I'm doing with that lot at the moment. But I have a month to work something out. Last year, this challenge produced an Atlantis/Casualty crossover, so quite honestly anything could happen!