Answer:
The Helldorado event celebration was launched in 1929 by Tombstone. As the town's economy was going down in 1920. Tombstone was awkward by its poor reputation, to regain investors and promoters' trust, this event was launched. Thus the economy regrows and the number of increases in tourists.
Moreover, Kelly and his fellow promoters was confident, that Tombstone's idea would be unique and will work to America's western glory. Then the problem occurred that some people killed in the gun shooting during Tombstone's Helldorado Days.
Explanation: