Bibarel has few things to set it apart from other Taunters: Super Fang and Unaware, and a good support movepool with stuff like Thunder Wave and Yawn. Bibarel can come into pretty much any sweeper that can't hit it for Super Effective and at least paralyse it or take a chunk out of its health with Super Fang. Something like SD Rain Kabutops, which can easily run through a team a +2, will be crippled by a Thunder Wave wielding Bibarel, since he doesn't care how many SDs Kabutops has up. Meanwhile, an Adamant LO Kabutops' Stone Edge will fail to OHKO, while Bibarel can just Thunder Wave to at least downgrade the threat of Kabutops. Bibarel is probably also one of the best counters to Cro-Pokemon (Regirock, Umbreon, Miltank, Uxie, etc) with the exception of possibly Spiritomb, since Unaware completely nullifies the boosts, allowing Bibarel to Taunt and Super Fang + Waterfall it to death.