Neutral
Neutrals are Transformers who have renounced the idea of factions or refused to take part in the Civil War. While some Neutrals resist joining a faction by choice, some defining themselves not by faction but by world, as the war drags on the majority are those who are unsuited to combat such as the Empties.
While Neutral is what the Autobots call them, the Decepticons prefer to call them "target practice".
Fiction
Marvel Comics continuity
G1 continuity
(Events from the UK-only comics are in italics.)
The Neutralist town of Yuss in the Stanix region was a frequent target for relieving the boredom of Decepticons stationed in the area The Magnificent Six!
Dreamwave continuity
During the evacuation of Altihex, twenty to thirty Neutrals took control of a building, arguing for both Autobots and Decepticons to end the War, renounce their allegiances, and unite. Skywarp took a moment to consider whether or not to take advantage of their idealism...then decided to slag them. The War Within, Part 1
Animated continuity
There would seem to be some robots within the Animated series who are neutral towards the conflict between the Autobots and Decepticons. While the good guys have blue eyes and the bad guys have red eyes, these guys are usually seen having yellow eyes in order to set them apart. Notable examples are Scrapper and Mixmaster, who kept going back and forth between the two factions before having their memories wiped by Bulkhead (but went with the 'Cons for a while, since they had better oil).
