Blue Leevers are a stronger variety of Leever that appear in dungeons and sandy areas like the Beach, Desert, and Gerudo Desert. Like other enemies, they can only move to the beat of the music, but differ in that they can move on every single music beat and can bury themselves underground.
Unlike their weaker counterpart, their fangs poke through the sand for only one music beat before emerging from underground. Though once above ground, they behave identically to the Leever by chasing either Cadence, Link, Yves, or Zelda for four beats before burying themselves underground and repeating the pattern.
Figurines of a Leever and a Blue Leever from The Minish Cap