Jumping from a tree with a running chainsaw is just plain dangerous!
Start it after you land.
Basement doors.
That will work.
The bad ideas are just flowing right now.
Back before the idiot city council put the Salvation Army and all the mugging transients a block from Sixth Street in Austin, there used to be some great Halloween parties there. One year a guy took the chain off of a chain saw and was firing it up in the crowd. The cops took it away from him because people kept panicking and running out in the street almost getting hit by cars. They gave him a receipt and told him he could pick it up at the police station a couple of blocks away the next day.