Mandibuzz has been revealed on a flyer for XY10 Awakening of Psychic Kings / Fates Collide. It is card #045/078 in the set. Thanks goes to @Biryu for the image and Bangiras for the translation!
A Mandibuzz BREAK promo will also be given out to those who purchase a booster box of the Japanese set.
[C] Bone Drop: Choose 1 of your opponent’s Pokemon that has an Ability. This attack does 60 damage to that Pokemon. (Don’t apply Weakness and Resistance for Benched Pokemon.)
[D][C][C] Cutting Wind: 80 damage.
Weakness: Lightning (x2)
Resistance: Fighting (-20)