TM91 (Flash Cannon) can be found in the Final Maze in MDTS. It may also be purchased in Kecleon Shops in all games in the Concealed Ruins, Mystery Jungle, and Lake Afar (even floors and floor 1) for 6500 Poké. In Explorers of Time, you may buy it on Mystifying Forest (even floors and 1 and 3), Mt. Travail, Happy Outlook (even floors and 1), Mt. Mistral (even floors and 1), Shimmer Hill (odd floors), and Midnight Forest (even floors and 1 and 3). It may also be sold in the Destiny Tower in Explorers of Sky. Additionally, TM91 can be found in Hidden Stairs in Lake Afar, Treacherous Waters, Southeastern Islands, and Inferno Cave in Explorer's of Sky.
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