This article presents the MUD as a form of ergodic literature from the perspective of literariness, outlining the features that allow us to distinguish a new literary aesthetic in this textual form. Starting from the works of E. Aarseth, Abbott H. Porter, David Golumbia, Esko Lius, Garry Crawford et al, we structure, in this study, the evolutionary deck of MUD forms, starting with the first MUD (by R. Trubshaw and R. Bartle) and continuing with the analysis of games such as: AberMUD, TinyMUD, OnLive Traveller, Diablo, Ultima Online, Myst, Riven: The Sequel to Myst, Second Life etc. The literariness of these MUDs is demonstrated by the narrative character of the in-game text, by the fact that the player evolves into the status of co-author and character, breaking traditional narrative conventions. The MUD produces a text-artifact, which gives the user both the pleasure of writing and the pleasure of reading, being the context for literature.