Evidence Left at the Scene

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Across
  1. 5. produced by plants and consumed by animals
  2. 6. 78% of earth's atmosphere
  3. 7. city where Ride the Cyclone takes place
Down
  1. 1. the theme of this crossword
  2. 2. gets the wrinkles out of clothes
  3. 3. key ingredient in exploding batteries
  4. 4. 24K magic
  5. 6. colorful lights