In this paper we ask the question, how can we define cheating in Massive Multiplayer Online Role-Playing Games (MMORPGs)? It is important to clarify immediately that what is at stake here is the way we study the phenomenon of cheating, how we conceptualise it and how we research it in MMORPGs. In particular, the focus is the difference between defining, or reducing, a phenomenon to its essential traits as opposed to defining it on the basis of the process that has generated it (see for discussions Latour, 1987 and 2005; Lash, 2002; DeLanda, 2002 and 2006). The rationale behind the opening research question is that much of the literature has defined cheating in online games via a restricted set of essential traits: in particular, as the player(s) actions that modify the game to obtain unfair advantages over other players. On the contrary, we propose that cheating should be conceptualised as what unfolds – the result(s) – from the empirical interrelations of several elements that compose MMORPGs, and not just from player behaviour. We provide a new perspective on cheating in MMORPGs, which suggests that cheating is the result of a dynamic process and interrelations between a range of elements. In this paper, we study cheating by using the concept of assemblage as proposed by DeLanda (2002 and 2006), following Deleuze and Guattari (1987). This concept takes a realist stance emphasising that social and natural phenomena should be conceptualised as the dynamic result of the empirical and historical relations among empirical elements, rather than thorough listing their essential traits or making timeless classifications. In this paper we analyse the following elements of MMORPGs and their relationships (but we are aware that the list is not necessarily conclusive): the game architecture, the game code and the game legal documents. Moreover, we focus on how these elements are interleaved with players, games companies and also companies offering cheating solutions. For us, cheating in MMORPGs possesses a mobile and permeable boundary where these different elements, and the players and companies strategies embedded in them, compete and / or cooperate – always in some form of relations with each other – in the process of stabilising or destabilising what is cheating in MMORPGs. We support this proposition by mainly providing empirical examples from ongoing research of the online game Tibia (http://www.tibia.com), a 2D, medieval fantasy MMORPG developed and distributed by CipSoft, since 1997. Tibia has an estimated 300,000 players and is played on more than 70 servers in Germany and the USA.