There are a series of alternate timelines occasionally posited and visited by the Course Books. These usually stem from key changes in the timeline involing Hunter Jusenkyou, and while not considered cannon, are fun to explore:
In The Trinity Alternative, Hunter meets 7 apparitions of himself from alternate timelines.
This version of Hunter comes from a timeline in which Hunter is stopped from going to Gudersnipe (a timeline glimpsed in The Fire Last Time), and is instead the lowly maintenance man at a rundown orphnage. In this timeline, he has a much more mechanical skillset, and uses his abilities to better the lives of the orphans.
But what if things had worked out differently?
–In this timeline, Hunter is smart enough to excel, and quickly learns how to manipulate people. He uses this influence to get accepted to a top university, gets his education paid for by some of his rich friends, and graduates to become one of the youngest C.E.O.s in history.
He forgets Amuro's training, turns down the invitation to Gudersnipe, and sets his sights on becoming a high-powered executive. When Komodo tries to seize control, Hunter draws upon his expertise and slays the dragon, thus becoming a national hero. He is obscenely wealthy and a complete jerk in this timeline.
This one hails from the timeline visited in Retrospectus from The Road to War, and is essentially a dark, evil version of Hunter, who murdered the Slayer Dragons and tried to take over the Multi-Verse. He came close to succeeding, but was stopped when Hunter and the Saratoga Crew accidentally stumbled into his timeline and allied with an alternate-version of Jason. In Retrospectus it is implied that this version of Hunter chiefly used technology; but in The Trinity Alternative he seems to be a Battling Sorcerer.
This version of Hunter comes from a substantially different timeline, whereof the key factor is never determined; however the most important part is that Sahar Jusenkyou is never murdered by Ryoga, and thus raises Hunter alongside Hygelic. Hunter grows up in Arindell in the shadow of the High Mountain Flight and is groomed throughout his whole life to be Pendragon and to lead the fight against Samuel Fate. This is the destiny whereof Hunter's father was so afraid, and that caused him to abandon Hunter when Sahar died. This version of Hunter also gives himself the enchanted sword Antebellum, which exists in the central timeline as well but is lost.
Pimp Hunter; he only gets one line in the story and is never mentioned again. It is implied that things are very different in his timeline.
Is a motivational speaker in his timeline, he also does not say much and like the sixth is mostly there for comic relief and to fill out the quota, ensuring eight Hunters in the scene.
There is a series of alternate timeline/alternate reality stories under the heading April Fools, written primarily as April Fool's jokes, but also for fun. Exploring alternate timelines allows for new avenues and new ways of thinking.
Lines is the working title for a short story from the April Fools section, which bends history to unite two characters who would not otherwise interact: Lily McConery of the Course Books and Ryo Sansen of the Antelope Books. This story is set during the Kamian Succession Wars, about 200 years before the events of the Course Books (thus during Ryo's lifetime), and takes place immediately following the events of Author of the Gust. This requires some bending of the time/space continuum, as this would be roughly 187 years before Lily's birth, so a little suspension of disbelief is required for the reader to enjoy the great story.
The basic premise involves Ryo and Lily meeting in a war-orphanage after both their homeworlds are taken over by the advancing Kamian line. They are moved to a planet at the far end of the Multi-Verse and separated from anyone they knew.