Halloween Set - Trick or Treat!

Our coach has come up with a fun idea for Friday's (halloween) workout. He is asking people to submit a 6 - 10 minute set that is either a "trick" or a "treat". He will put all of the responses in a hat and choose. Sounds like fun!! I haven't come up with a treat set yet, but my trick set is 2 reverse 200 IM's, second one faster than the first with ten seconds rest. BTW this is LCM. What ideas do you have?