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>Chatter inflicts damage and may confuse the target. If the move has recorded audio from its field move functionality, that audio will play for the move's sound effect instead of Chatot's regular cry
>If Chatter has no audio data (as is the case for wild and NPC-owned Chatot), the chance of confusion is 1%. Otherwise, the chance of confusing the foe is determined by the volume of the recording
>Generally, the higher the volume of the recording is, the higher the chance of confusion
this is exclusive to the 4th generation of games btw