Mr. E/Tropes

A-G
0% Approval Rating: Mr. E isn't liked by anyone in the cast, and he doesn't care. He merely wants his goals fulfilled, and will use any means to ensure this. As stated by Darkrai's girlfriend, this effectively makes him Congress.

Animal Motifs: The Baboon. Mr. E even wears a baboonskin cloak.

The Chessmaster: Mr. E is this for the series as a whole, manipulating the cast like chess pieces on a board. He also actually plays the game.

The Faceless: So far.
 * Common Knowledge: Darkrai's friends in the TARDIS found out what Mr. E would look like long before it's actually revealed.

H-P
Hidden Agenda Villain: Very probably- pretty much.

Magnificent Bastard: Oh hell yes.

Manipulative Bastard: Very much so.

Mask Power: Probably. It's implied that E is very powerful.

Meaningful Name / Punny Name: "Mr. E". Exactly who he is is just that, a mystery.

Odd Friendship: With Exialia. Perhaps some romance?

Playing Both Sides: E has no loyalties, only goals.

Q-V
Troll: Pretty much the only explanation for his interactions with Vivian.

X-Z
Xanatos Gambit: ...Pretty much anything he's involved in winds up being a mild example of this.