I need scenarios for mock NRP codes...

My boss asked me to run mock codes for the night shift. I'm very excited about this, I think it'll really help keep up our skills. I'm looking forward to springing these on my coworkers as they have no idea I've been asked to do this. I could uses some help coming up with a big list of scenarios, ranging from not so horrible to your worst nightmare. Especially your worst nightmare! Thanks!