Outhouse Books presents Trick or Treat. Do you know the origins of Halloween? Did you know that pumpkins can be blue? Do you know the name of the last cavalry battle fought on Halloween? Well, trick or treat This collection of Halloween facts and trivia will let you become the next Dr. Frankenstein of trivia. With a history of Halloween, its symbols, and trivia about everything associated with Halloween, you will get king size knowledge about October 31.