A ranter is an individual (normally in a position of power) who is prone to ranting in rage when he or she encounters a situation (or is informed about a development) that displeases them immensely. Their informer and objector are almost always the cause of their ranting - informing them of negative developments or objecting to their plans respectively, resulting in a burst of fury.
The most prominent ranter in the parody universe is Adolf Hitler, who possesses his own entourage of informers, objectors, occasional ranters (see Joseph Goebbels) and hugely incompetent generals. His fits of screaming in impotent fury are the foundation of the infamous parodies. However, other dictators (such as Stalin) are also known to rant and possess entourages consisting of informers, objectors, ranters and other buffoons and colourful characters.