<P> Changes this season include the introduction of the 18 - foot (5.5 m) "Mega Wall". It is next to the original 14'6" (4.4 m) warped wall, and give competitors the choice of which to climb . Competitors who choose the Mega Wall have only one attempt to reach the top, and if successful, will win $10,000 . If unsuccessful, the competitor will only get one shot at the warped wall . Those who do not wish to attempt the Mega Wall have three chances to reach the top of the warped wall . The Mega Wall will only be featured in the city qualifiers . In addition, the age limit was lowered down from 21 in all previous seasons to 19 this season . The "Last Ninja Standing", the competitor who goes the farthest in the finals, if no one completes stage 4, will now receive $100,000 . </P> <P> Season 7 champion Isaac Caldiero participated and finished the Indianapolis qualifiers, marking his return to competition in the series . He would later fall in the city finals . </P> <Table> <Tr> <Th> Qualifying airing </Th> <Th> Finals airing </Th> <Th> City </Th> <Th> Episode taping </Th> <Th> Venue </Th> </Tr> <Tr> <Td> June 6, 2018 </Td> <Td> July 16, 2018 </Td> <Td> Los Angeles, California </Td> <Td> March 6--7, 2018 </Td> <Td> Universal Studios Hollywood </Td> </Tr> <Tr> <Td> May 30, 2018 </Td> <Td> July 23, 2018 </Td> <Td> Dallas, Texas </Td> <Td> March 25--26, 2018 </Td> <Td> Fair Park </Td> </Tr> <Tr> <Td> June 13, 2018 </Td> <Td> July 30, 2018 </Td> <Td> Miami, Florida </Td> <Td> April 13--14, 2018 </Td> <Td> Bayfront Park </Td> </Tr> <Tr> <Td> June 18, 2018 </Td> <Td> August 6, 2018 </Td> <Td> Indianapolis, Indiana </Td> <Td> April 29--30, 2018 </Td> <Td> Monument Circle </Td> </Tr> <Tr> <Td> June 25, 2018 </Td> <Td> August 13, 2018 </Td> <Td> Philadelphia, Pennsylvania </Td> <Td> May 11--12, 2018 </Td> <Td> Richmond Power Plant </Td> </Tr> <Tr> <Td> July 9, 2018 </Td> <Td> August 20, 2018 </Td> <Td> Minneapolis, Minnesota </Td> <Td> May 25--26, 2018 </Td> <Td> U.S. Bank Stadium </Td> </Tr> </Table> <Tr> <Th> Qualifying airing </Th> <Th> Finals airing </Th> <Th> City </Th> <Th> Episode taping </Th> <Th> Venue </Th> </Tr>

When are the finals of american ninja warrior
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