In numerous episodes of Buffy, the Mutant Enemy logo (the little monster seen at the end of each episode) changes in some way:

In Becoming (Part 2), he says ‘I need a hug’.

In Amends, he is wearing a Christmas hat.

In Graduation Day (Part 2), he is wearing a graduation hat.

In …

The Mutant Enemy monster seen at the end of the credits is altered in the episode Amends. He wears a Santa cap, and there are bells jingling in the background.

Tara gives Giles a little rubber monster as a leaving present in Bargaining (Part 1) and says “Grrr…argh”, which is clearly a reference to the monster in the Mutant Enemy logo seen at the end of every Buffy episode.

At the end of Becoming (Part 2), the Mutant Enemy monster (seen after the end credits) says, “I need a hug.” The events of the depressing episode were just too much for him.

Joss Whedon supplied for the voice for the Mutant Enemy monster who says “Grrr….Argh” at the end of each episode. Mutant Enemy is Joss Whedon’s production company. He took the name from a Yes song called “And You, And I”. Mutant Enemy was also the name he gave to his …

The Mutant Enemy monster joins in the singing at the end of the episode Once More, With Feeling.

David Soloman was the person who moved the Mutant Enemy monster across the screen, which can be seen at the end of every episode.

In the episode Chosen the Mutant Enemy monster turns briefly to the camera at the end of the episode.

The Mutant Enemy monster is sporting a graduation cap at the end of the episode Graduation Day (Part 2).

The Mutant Enemy monster says “We are Gods” at the end of the episode Storyteller.