In the format or formats you believe better.
For NU:
Braviary can effectively perform the role of a wallbreaker or late-game sweeper thanks to its access to utility moves like Bulk Up and Roost, above average bulk, and great Attack. In addition, its great coverage between just Brave Bird and Superpower leaves it walled by very few Pokemon, meaning it can be very difficult to answer defensively. Braviary can also provide great support for its team, since its ability Defiant dissuades and punishes the use of Defog. Additionally, the sheer special bulk of the Substitute + Bulk Up set lets Braviary check Grass-types like Sceptile and Whimsicott as well as other special attackers like Guzzlord and Accelgor. Unfortunately, Bulk Up variants of Braviary are easy to check defensively with Pokemon such as Rhydon and Steelix and rely on moves that cut into their longevity, leaving them more easily revenge killed. Braviary also deals with a weakness to Stealth Rock, limiting the number of turns it can safely switch in before having to recover with Roost and thus providing the foe with a free turn. Faster offensive Pokemon like Heliolisk and Mega Glalie also give Braviary problems, as they can easily take advantage of Braviary's lesser Speed and OHKO it.
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