Mega Gyarados uses the Mold Breaker Ability, which ignores the abilities of the foe when attacking.
Mega Gyarados can be obtained by using the Mega Stone while Gyarados is holding a Gyaradosite in battle.
Mega Gyarados has yet to appear in a Spin-Off game as of writing.
Trading Card Game
Mega Gyarados resides in the Borderline (BL) tier of competitive battling, meaning it does not receive enough usage to be in the Overused (OU) tier but is too broken to stay in the Underused (UU) tier. Thanks to its access to a solid Dark-type STAB move in Crunch and a very high 155 base Attack, Mega Gyarados can make for a terrifying sweeper with Dragon Dance to patch up its subpar speed. With great bulk and good resistances prior and after Mega evolving, Mega Gyarados finds numerous opportunities to set up and wreak havoc on opposing teams. Mold Breaker allows Mega Gyarados to ignore certain abilities like Sturdy, Unaware, and Water Absorb. It does suffer from lacking reliable recovery and being weak to Stealth Rock prior to switching in, but Mega Gyarados is a phenomenal offensive sweeper that can punch massive holes through teams when given the correct support.
Mega Gyarados is also a viable option in the Ubers tier of competitive battling. Thanks to Mold Breaker, Mega Gyarados can bypass certain abilities such as Multiscale, Magic Bounce, and Sturdy, which can make it a decent sweeping option to counteract defensive teams. It can hold its own against more offensive teams due to its ability to check Primal Groudon and Ghost Arceus, but it does not offer much defensive synergy otherwise and needs to be wary of the latter's Lava Plume attacks that could burn it. Thanks to nice bulk and a strong 115 base Attack, Mega Gyarados is fully capable of pulling off a Dragon Dance set with Taunt to prevent Pokémon like Mega Sableye from inflicting status on it. However, Mega Gyarados is hindered by the presence of Xerneas and Mega Salamence, both very common and threatening Pokémon. Mega Gyarados takes up a Mega slot which can go to a number of other threatening Pokémon, including the aforementioned Mega Salamence which holds its own against the offensive builds that dominate Ubers.
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