Twisted Wizard (known as Twisted Wizard Black in online version), is one of Greg's favorite video games. He was going to get it one Christmas, but his present was mixed up with a present for the Giving Tree Guy, so his mom bought him a new copy of Twisted Wizard. Instead of getting Twisted Wizard, he got a sweater. According to the online version, his mom bought him a replacement copy, but only after Greg wrote all his thank you notes. It is a game using a machine similar to a Sony PlayStation 2, and is described as being "impossible to save" in the online version of the first book. However, in the movie, it is clearly a Nintendo Wii game. In the movie it is obviously a fantasy game, it seems to have some form of currency (shown in the bottom-left corner of the players' screens), and it seems to have been inspired by Skyrim and The Witcher series of games, since all of them have similar elements, and all belong to the fantasy genre.

The game is an RPG about a wizard, Tothlon, who is left injured and robbed by his apprentice, Santal, the twisted wizard of the game's title. The first game is about Tothlon's quest to find the Thorian Wand so he can defeat Santal, meeting several fellow wizards who join him on his quest along the way. The first game ends with him claiming the wand from its dragon guard, while Santal, imprisoned by Tothlon in a magic mirror, watches. The sequel is about Santal escaping with the help of Manao, a fire demon, after a deal saying that once Santal is freed, he can lead the demons to victory against wizard-kind. Tothlon and several other wizards must stop them using the Thorian Wand, but they must gather six other wands, each made by a different Norse God, first. In the end, the demons are sent into the void dimension (0D), but pull Santal with them. The prequel, as of The Ugly Truth, is soon-to-be-released, and will be the first game not to feature Santal, instead featuring Tothlon's journey as a young apprentice to stop the evil practices of his master.

Greg always beats Rowley in Twisted Wizard, with the exception of Dog Days, where Rowley injured Greg and hindered his ability to play, thus beating him in a competition held at Game Hut and winning the "grand prize" of a large box of chocolate-covered raisins or a chance move on to the national championships.


In Poptropica, an island called Wimpy Wonderland based on Cabin Fever has been made, and in it you can play Twisted Wizard, in the game you are wizard who has to cover himself with blocks and have to prevent monsters from destroying the fortress and if they destroy it, you lose.