Santa Claus is a minor character on Inanimate Insanity. He has the typical appearance of the holiday Santa Claus, with a red suit, white beard, and red santa hat.
In The Snowdown, Santa does not appear until the very end of the episode. However, he is discussed very much by the characters. In the beginning of the episode, Apple talks about how that she's excited to get her pony from Santa for Christmas, to which Paintbrush breaks the news to her that Santa isn't real. At the end, he is shown coming down and picking up a note from MePhone. It reads that he has laid out milk and cookies for him, but actually, he writes that there are no cookies since he's a fat slob so he ate them. Santa is disappointed at the failure of the simple task that is the only material reward he gets from delivering presents when Apple approaches him. Santa recognizes her, and Apple states that she knew he was real, and then proceeded to ask where her pony was. Santa, having forgotten to bring it, runs away.
In Aquatic Conflict, while he does not appear, Santa is mentioned briefly in this episode. When Apple says that she hopes Paintbrush is eliminated, Paintbrush yells back that she/he wishes Santa took Apple with him.