In-game, Bibarel is phenomenally useful as an "HM slave" and is highly recommended for any team. Unfortunately, that usefulness doesn't transfer over into the competitive scene. While Bibarel has an amazing offensive STAB combination, its shallow usable movepool and base stats leave a lot to be desired. However, Bibarel has a saving grace on the battlefield as an awesome Baton Pass recipient thanks to its unique ability, Simple.
Although it has been cursed with a dull movepool and depressing base stats, Bibarel possesses an amazing ability, Simple. When combined with excellent dual STAB attacks that are only resisted by Shedinja in UU, Bibarel makes an impressive Baton Pass receiver.
In preparation for a Bibarel sweep, you must know two important things. Firstly, Simple doubles the effect of stat boosts, and the effect is the same when Bibarel receives boosts from a Baton Passer. Secondly, in reverse, Simple also doubles stat drops that Bibarel receives. This could be unfortunate if Bibarel or your Baton Passer is caught on the end of an Intimidate. One can prevent Bibarel's intended Attack boost from dropping before it is passed by using a Baton Passer with the ability Hyper Cutter. The most notable example of this is Gligar, who is able to pass both Agility and Swords Dance boosts.
With Return, Bibarel tears through walls like tissue paper, OHKOing Uxie, Weezing, and Milotic with Stealth Rock damage. Waterfall takes care of Steel-, Rock-, and Ghost-types, OHKOing Steelix, Regirock, and Spiritomb. Quick Attack is a viable option to beat Sucker Punch and all other priority after Bibarel is passed a Speed boost. The final move comes down to what specific actions you would like Bibarel to perform. Taunt will keep Haze, phazing moves, and status away from Bibarel, while Toxic will help make Bibarel more useful should it be forced into battle before acquiring multiple boosts. Superpower can be used as an emergency Registeel removal; however, the Attack and Defense drops are doubled, so its use is highly cautioned.Team Options & Additional Comments >>>
Aqua Tail and Double-Edge can replace Waterfall and Return on the Baton Pass recipient set, respectively. However, Aqua Tail's lower accuracy could prove fatal to Bibarel's sweep should it miss, and Double-Edge's recoil could easily deplete Bibarel's HP too quickly. Plus, Waterfall and Return already achieve all of the KOs Bibarel needs. The only other physical options available to Bibarel are Focus Punch and Superpower. Neither provides Bibarel with any extra coverage, and Superpower's Defense and Attack drops are doubled thanks to Simple. Bibarel can go the special attacking route as well; however, Bibarel's Special Attack stat sits at a meager base 55. Charge Beam, Grass Knot, Ice Beam, Surf, Thunderbolt, and Shadow Ball round out Bibarel's special movepool.
Bibarel also has boosting moves in Curse and Amnesia; however, Bibarel is not fast nor bulky enough to set up by itself and can make much better use of Speed and Attack boosts passed to it. Super Fang should only be used should Bibarel not receive any boosts, as Bibarel is capable of straight up KOing the strongest walls of UU with the appropriate boosts under its belt. The rest of Bibarel's usable movepool consists of Stealth Rock, Yawn, and Thunder Wave. While all have their uses, Bibarel is much better off attacking and making use of its offensive prowess than supporting the team.
Checks and Counters
Should Bibarel be successful in receiving both a Swords Dance and an Agility boost, little in UU can stop a Bibarel sweep. Registeel stands the best chance of not being OHKOed by Bibarel's assaults; however, it has no way of OHKOing Bibarel back. Keep in mind that Registeel should not attempt to use Thunder Wave as Bibarel will more than likely use Taunt on Registeel before it can paralyze it. Hitmontop, Blaziken, and Toxicroak can attempt to snipe Bibarel with Mach Punch and Vacuum Wave, but Quick Attack will do a number on all of them. Shedinja is completely immune to both of Bibarel's STABs and can put a stop to a Bibarel sweep. However, Bibarel can bypass Shedinja with Pluck or Toxic, and entry hazards will prevent Shedinja from even entering battle. Tangrowth has a chance of surviving a Swords Dance-boosted Return with Stealth Rock down and can proceed to either put Bibarel to sleep or give it some major whiplash with Power Whip.
Without any boosts, Bibarel is nothing more than a sitting duck. Electric-types such as Manectric, Rotom, and Lanturn can fry any Bibarel with Thunderbolt; Grass-types such as Venusaur, Exeggutor, and Leafeon can slap Bibarel with their Grass-type attacks; and finally, Fighting-types such as Hitmonlee and Hariyama can pound Bibarel into oblivion with their STAB attacks.