Chingling

Diamond: It emits cries by agitating an orb at the back of its throat. It moves with flouncing hops.

Pearl +2: Each time it hops, it makes a ringing sound. It deafens foes by emitting high-frequency cries.

Platinum +6: There is an orb inside its mouth. When it hops, the orb bounces all over and makes a ringing sound.

HeartGold / SoulSilver: It emits high-frequency cries that people can’t hear. Once it starts, it can cry for an awfully long time.

Legends: Arceus: This Pokémon gave me an excruciating headache when it seemingly cried out without making a sound. Perhaps there are some sounds that the human ear is simply incapable of hearing.