Knight of Cerebus

A Knight of Cerebus, is a type of villain who appears in comedic or light-hearted media, in which villains are not meant to be menacing, but creates a stark contrast by being played completely seriously, changing the tone of the story. To clarify, when a story portrays usually bumbling, comedic or incompetent villains, or even villains who despite posing a credible threat still have comedic moments, the Game Changers are very competent, really dangerous, sometimes even frightening, and have a much bigger impact. Episodes featuring them focus on the seriousness and drama and not on humor.

For a villain qualify in this category, they must provide situations that are much more serious or threatening than any other villain that has appeared in the same story. The very appearance of one can change the tone of the series for good and/or shatter the status-quo.

Good examples for this are Frieza from Dragon Ball Z, Aya Tokoyogi from Strike the Blood, Hunter J from Pokemon and Slade from Teen Titans are seen as more competent than the rest of the villains.

Guidelines:

1. They are hardly if ever comedic. Of course there are very rare exceptions namely if their gimmick is that of a clown or jester in which that is simply part of their gimmick itself. This cannot distract or lighten the mood.
2. This is not simply a Dark character. It has to be of an unheard level, like a serial killer in My Little Pony or similar very lighthearted media.
3. There are very few if any of these within a story or said media, and if you have had one it is much harder to have another one later due to a couple of reasons. After one is introduced, it is harder for another villain to standout enough to truly count. The other reason is that the audience in general isn't as easily shocked and at times even expect more like them.
4. This villain type must ultimately contrast to the current setting of the story, and their very presence darken it as a result. This feels strange and is previously unheard of within the setting.