The Adult Terrapus is the most commonly encountered enemy in Deepworld. It will attack the player on sight with inky projectiles. When mining underground, the Adult Terrapus may pop out of dirt blocks randomly. Killing the creature will provide you with giblets.
The Adult Terrapus is a feisty enemy - agile, hard to aim at, and certainly just plain annoying. So how do you take him down? Simple - use any weapon (be it gun, sledgehammer, or pickaxe) and give it your all. Sure, you'll also have to dodge incoming projectiles that fly at you at insane speeds, but you'll make quick work of the Adult Terrapus no matter what. Now, if you don't want to risk an encounter, simply dig twisting tunnels through the dirt, confusing the Terrapus and allowing you to make a quick escape.