Moves

Taunt allows Mega Banette to stop entry hazard setters dead in their tracks, while also shutting down any offensive leads that attempt to set up. Prankster Will-O-Wisp is used to get a quick burn, crippling physical attacking foes. Alternatively, slowing threats down with Thunder Wave can help Mega Banette outspeed them and hit them with its own attacks. STAB Shadow Claw deals good damage coming off of its massive base 165 Attack, but Shadow Sneak can be used for priority and picking off weakened foes. Alternatively, Knock Off can be used to remove a foe's item. Destiny Bond works incredibly well with Prankster; if all else fails, this is your kill switch. Frisk allows you to scout for items such as Focus Sash, Assault Vest, and Leftovers that Knock Off can remove.

Set Details

252 EVs are invested in HP since Mega Banette needs to be able to take a hit to make up for its low Speed and frail defenses, while 252 Attack EVs allow it to hit relatively hard. Running Frisk on Banette allows you to scout out the opponent's items to get a sense of what they're planning: finding items such as Berries, Choice items, and Focus Sashes will give you an idea of how the opponent will use that Pokemon. Banettite is the best item for Banette; not only does Banette get a 100-point boost to its base stat total, but it also gains the much needed Prankster, which is the only reason that Mega Banette is viable in the first place. Lastly, Mega Banette will want to run an Adamant nature to ensure that it can take full advantage of its newfound Attack without sacrificing Speed or bulk. An alternate spread of 148 HP / 252 Atk / 108 Spe can be used in order to allow Banette to outspeed Pokemon like Suicune and effectively spinblock against Blastoise, granted that the opponent doesn't predict the switch in. However, this spread reduces Banette's overall bulk, so it should be used to remove Blastoise if hazard blocking is necessary for your team's success.

Usage Tips

Mega Banette doesn't gain Prankster on its first turn, so try to Mega Evolve it as soon as possible. Mega Banette works well mid-game, when it can whittle down the opponent's team with Will-O-Wisp. Use Taunt on the foe to prevent them from setting up when they predict you to use Destiny Bond or Will-O-Wisp. Prankster Destiny Bond allows you to instantly shut down a sweep only once, so use this wisely. However, most of the time Destiny Bond is obvious, so it's always important to figure out when to use it, since it's sometimes difficult to determine whether an opponent will attack, use a status move, or set up. Avoid wasting Destiny Bond on weakened Pokemon; conserve it to get rid of stronger foes. Using status moves and switching out can be great for allowing bulkier teammates to set up on burned or Taunted Pokemon, so burning or paralyzing a foe and then making a switch can really put pressure on an opponent while giving you the edge.

Team Options

Due to its limited movepool, Mega Banette can't provide its teammates with too much help, so it relies more on its team members instead. Mega Banette is vulnerable to Dark-types, so having bulkier teammates like Cobalion or hard-hitting teammates like Lucario to take a Knock Off is appreciated; not only can it benefit them if they have the Justified ability, but it can also get Mega Banette out of difficult situations. Other good teammates that can take hits are Florges and Umbreon, as they both resist Dark-type moves. Florges has great Special Defense, while Umbreon can take both physical and special attacks nicely. Florges and Umbreon can also provide support for Banette with Wish and Heal Bell / Aromatherapy in case you want Mega Banette to last longer and wreak more havoc.