Alter Environment was a Force power that involved various techniques that allowed the user to manipulate nature, enabling the creation of phenomena such as Force whirlwinds or fog that could be used to attack or to shield the user from opponents. Plo Koon further modified this ability with his considerable knowledge of physics. Streen and the Sith Emperor were notable adepts of these talents. The Sith Emperor used this ability to corrupt the environment of the planet Dromund Kaas.