With 125 Attack, 100 Speed, a myriad of moves + Swords Dance, Mercenade is sure to be a powerful contender on any team.
Having coverage like Earthquake from its pre-evolution, or Leaf Blade, X-Scissor, Psycho Cut, Devastate, etc. leaves it with many options for covering type weaknesses that the rest of your Pokémon may struggle with. Steel/Fighting is an incredible typing to work with, covering many types just by STAB alone.
While Hustle is more risk than reward, Intimidate is an excellent ability that makes leading off with Mercenade quite a powerful choice. All of these tools let it outclass the far slower evolution, Mandiblade.
Rock Polish and Drain Punch are excellent contenders if you wish to run an Adamant one, while Hone Claws is better off for its secondary ability.
Unfortunately, Mercenade suffers from four-slot move syndrome and not having access to Rock Head for taking advantage of Double-Edge. It also does not possess Sand Veil, an incredibly strong ability for Sandstorm teams, like Mandiblade does.
But its lack of ability usage is made up for far greater with its utility and ability to pivot into physical sweepers and set up. Mercenade's 65 Special Defense also leaves something to be desired, so be careful of switching into Special Attackers.
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