Just wanted to have a friendly discussion on these. Here is the definition that I could find for both: From what I understand of Deus Ex Machina, its basically a cheap plot device where some object or thing is used as the be-all and end-all thing that drives the plot. Either a doomsday device or the last artifact of hope. I'd classify almost every single TF thing in the TF mythos as a Deus Ex Machina - Plasma Energy Chamber, Oracle, Key to Vector Sigma, Matrix, Allspark, Well of Allsparks, etc. From what I know of MacGuffin, its something along the lines of a Deus Ex Machina in that it is created purely to advance the plot. Artificially. Sam's grandpa's glasses is a use of a MacGuffin. Its used as a plot device to make the characters act in a certain way. I don't think either of these are necessary. I think a plot can happen fine without any of these elements. Look at anything from a war movie to a drama - there are no plot devices used like the above. I know we as TF fans have been barraged with this stuff lately, but do we really need this? Sure, I could see ONE Deus Ex Machina - along the lines of the one ring in LOTR - but do we really need one more stronger than the other? Do we really want to go the route of bad anime with someone is strong because their "power level" is greater than anyone else's only to find someone later on that is "even more" powerful and continuing ad nauseum? I think the focus has comptely been consumed by these cheap writing tactics. There are an infinite amount of new ways that TFs could be portrayed if someone just uses their imagination in clever ways. What is so bad about the motivation being simple? What if it is just a simple battle? What if the entire universe isn't in danger - does that make the plot somehow less?