Chaotic Evil

Chaotic Evil is one of the Nine Alignments, combining Chaos with "Evil" (malevolent intentions, being oriented towards the Dark Side, etc.), both a game mechanic, and an actual concept within the universe of the franchise itself.

Description
Chaotic Evil characters are agents of darkness and chaos, bloodthirsty harbringers of destruction full of greed, hatred and lust for destruction. They are violent, hot-headed, arbitrary, unpredictable, ruthless and brutal. Luckily for the Forces of Good (or Lesser but more Rational Evil), Chaotic Evil characters are typically lacking in long-term ambition (usually more driven by momentary lust for pleasure, blood or destruction), but even more ambitious representatives of Chaotic Evil tend to produce haphazard plans that are easily thwarted by the Forces of Good or Lawful Evil. While even Lawful Evil characters are prone to backstabbing their own allies, they typically make fairly accurate cost-benefit analyses about the benefits of working together towards a shared goal, and thus organize their teams accordingly - not so much with Chaotic Evil, who produce poorly-organized groups that can only be held together with force: even the mightiest leader must expect to be backstabbed, and must keep his subordinates in line with torture and terror, lest they get any funny ideas.

Chaotic Evil characters despise all that is natural, beautiful and orderly. While Lawful Evil and Neutral Evil ultimately desire power (typically for selfish reasons), Chaotic Evil desires destruction - very often, the destruction of the whole world as we know it. The earlier two can be ultimately reasoned and negotiated with - the latter, not so much.

Observance
Care must be taken when classifying individuals, classes and entire races as "Chaotic Evil" - one man's "Chaotic Evil" is another man's Lawful Neutral or even Lawful Good. Demons are frequently described as "Chaotic Evil", at one point, even Orcs were considered "Chaotic Evil", however, both are in fact bound by their own laws and, making them Lawful Neutral at worst. (definitely not from the the church's point of view tho, who still consider both to be Chaotic Evil).

Chaotic Evil in its truest form is a fairly rare alignment, most usually represented amongst violently insane people, or mentally broken people who have crossed the and thus completely lost their will to live for anything other than vengence. A victim of mental torture who loses their sanity and redefines the meaning of their life as "kill, kill, kill" is Chaotic Evil. A crazy wizard who seeks to destroy the whole world is considered a good example of Chaotic Evil. Despite not even being sentient to begin with, artificially crafted monsters who attack any living creature on sight are frequently associated with and considered the prime examples of Chaotic Evil.

Characters who say that "chaos is a ladder" are not Chaotic Evil - they are Neutral Evil or even Lawful Evil. Nevertheless, Chaotic Evil characters may serve as useful (and disposable) pawns for Neutral Evil and Lawful Evil characters - especially for the ones who do in fact believe that "chaos is a ladder".