Like the totems, Lusamine's Pokemon when she's possessed, the wild Ultra Beasts, the mid-game Nihilgeo boss, etc.
Aura Break inverts the effects of Fairy Aura and Dark Aura: instead of multiplying the power of Fairy- or Dark-type moves by those Abilities' normal multiplier of 1.33, the power of moves of that type is divided by 1.33 instead, resulting in approximately a 25% decrease in power as long as both Abilities are active.
No, Aura Break does not reverse the effects of any other auras. It only reverses the effects of Fairy Aura and Dark Aura.
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