Mazes and monsters is a parody of Dungeons and Dragons.
When Dee Dee asks Dexter what character he wants to be, Dexter begins to tell her that he wants to be "Gygax, the level 27 warrior". The name is a reference to E. Gary Gygax, the man who invented the original Dungeons and Dragons.
The name of Dexter's character "Hodo" is a reference to Frodo from Lord of the Rings.
This is the first 11-minute episode in particular.