Make a puddle of water and put the guest in it. After
about five seconds, a message will state that they died.
Make a roller coaster or a ride like the Inverted Vertical Shuttle,
Launched Freefall, or Powered Launched Coaster. Make a roller
coaster that is short of track, set the speed to its highest,
and put the waiting time for full load. The coaster will explode
and kill all the riders.