Tympole

Black: They warn others of danger by vibrating their cheeks to create a high-pitched sound.

White +2: By vibrating its cheeks, it emits sound waves imperceptible to humans. It uses the rhythm of these sounds to talk.

Black 2 +3: By vibrating its cheeks, it emits sound waves imperceptible to humans and warns others of danger.

Sword: Graceful ripples running across the water’s surface are a sure sign that Tympole are singing in high-pitched voices below.

Shield: It uses sound waves to communicate with others of its kind. People and other Pokémon species can’t hear its cries of warning.