Sand Sharks

Sand Sharks are Hardmode enemies found in the Desert Biome only during a Sandstorm. They are able to "swim" through all varieties of Sand, Hardened Sand, and Sandstone Blocks, but will collide normally against any other block. When they draw near a player, they will lunge out of the sand to attack.

The Sand Shark itself only appears in ordinary Deserts. There are other variants for different versions of the Desert:
 * Bone Biter in the Corrupted Desert
 * Crystal Thresher in the Hallowed Desert
 * Flesh Reaver in the Crimson Desert

Trivia

 * Cenx confirmed that the inspiration for the enemy was a joke with Safemanda's daughter.
 * The sound the dash attack makes seems to be the same as the sound from the Vampire.