Alternative Timelines

As of A Glimpse at What May Be it is revealed that Mige is a "Traveler"; one with the ability to "travel" to different points in time. Throughout Pokemon: New Horizons, Mige has had the opportunity to travel to and view several possible futures.

Mige the Traveler

^{Main article: Travelers}
The nature of time travel or the full capability of a Traveler are not understood so far. It seems as if being a Traveler can manifest in different ways, or rather, different Travelers possess different capacities for traveling. For example, Mige's Traveling seems to be limited to Consciousness Shifting, while other Travelers like Hermit can apparently physically travel in time. It's unclear at the current time whether this is due to Mige's inexperience, or some other limitation.
When Mige uses his Traveling abilities, it is always when he is asleep. Specifically, he seems to automatically trigger this ability when he hits REM sleep. This doesn't happen every since time he sleeps, or even every time he hits REM, but hitting REM seems to be a requirement for the moment.
After triggering his ability, Mige does not seem to have much control over his destination, nor how long he spends there. He can sort of "aim" himself by concentrating on a specific day, but he it's far from reliable. In terms of the duration of his trip, there does not seem to be any clear indicators as to why he spends any amount of time in a given future; he has spent as little as 30 minutes in one timeline, and up to several hours in others. So far, Mige has only traveled to the future, but the Rules he sent himself seem to imply he may be able to go to the past one day.
While in the future, only Mige's consciousness has shifted. So far, his future self is also always waking up, so REM on both ends may be needed right now. He seems to "possess" his future body, for lack of a better term, and is limited by the body of his future self. For example, he has felt the aches and pains of age when he travels far enough in the future.
In the future, Mige can interact and investigate freely, though his future self often takes measures to prevent his past self from discovering too much too soon. When he's preparing to return to the present day, his left hand begins to tingle--the intensity slowly increasing the closer it gets to him returning. His hand tends to be numb for a few minutes when he wakes up in the present.
Recently, Mige has shown the ability to bring people from a potential future back to the present, as demonstrated in NH026 when he brought Alice back to the present, albeit briefly. It's unknown if he can do with this anybody or if they must also be a traveler.
Mige never knows what he is going to find or experience in any given Timeline. According to Theron, a future version of Clem, when Mige travels, he goes to the future that is "most likely as of that specific moment". Theron also explained that a great deal can affect this destination.

Rules

Mige seems to have certain rules he must abide by when he travels, and these rules seem to be both lax and strict at the same time. All futures have information that they "can't tell" Mige. According to a future version of Celosia, future-Mige tends to be very adamant about others following these rules as well. This does seem to be, at least in part, due to the fact that 'time is fragile' and too many needless changes could be harmful. But another part of it seems to be more strategic; trying to ensure certain things occur in a certain way or order, which may require a certain amount of secrecy.

Notation

For the sake of simplicity and consistency, timelines are noted numerically; they are numbered in the order that Mige traveled to them.
The timeline experienced in the present day within the World of Pokemon universe, as experienced by Mige and all other characters, is referred to as the “Prime Timeline”, the “Prime World”, or “Earth Prime”. As such, current, present-day versions of characters are referred as their prime versions. So for example, the Mige that lives and acts within the "present day" is Mige-Prime.
The rest of the timelines are numbered numerically in the order in which Mige has visited them. Characters encountered within these timelines are referred with that number, so Kai-003 would be the version of Kai that exists within the future timeline of Timeline-003.
It should be noted that some timelines, but not all timelines, have been given nicknames or titles, often by Mige himself and some by other characters within the story. For example, most characters refer to Timeline-002 as "Vigilante Earth" or "the Vigilante Future".

Timeline-001

^{Main article:Timeline-001}

The first timeline that Mige visited and the one we know the most about. In this future, many of Mige's friends have died, including Bill, Jenn, Tim, and most importantly, Crystal. Mige and Celosia raise Clem and, after having a son of their own together, marry. In this timeline, Mige has lost many people that he cares about and Team Relic was stopped, but not before they unleashed some kind of ecological disaster.
As time passed, Mige and Celosia also had a daughter, and their family lived in Kanto for more than 11 years. In 2036, Mige accepted a position as the Kalos Professor when Professor Sycamore retired, and Mige left the cottage in Cape Cerulean to Clem.
At some point before 2030, the world suffered something Theron refers to as "the Calamity". While this is implied to take place in most timelines, we only have information on it from this timeline. According to her, a meteor suddenly appeared just beyond the moon. It was undetected before that time, making the people of earth unable to respond. The meteor crashed into Hoenn just under two hours after it was first detected, bringing both devastation and a terrible plague.
Mige died in 2041 from "a sickness", which is presumed to be the plague mentioned above, though Mige's habit of smoking contributed at least in part. By 2044, the world was "doomed". Out of desperation, Celosia-001 and Clem-001 hatched a "last ditch, absurd" plan to save the future by sending Clem back in time. Celosia-001 was able to "crack" time travel and they planned to send Clem on a one-way ticket back to 2020. Celosia wrote a letter for Mige-Prime, mostly containing memories of their life together.
However, Will Darrow attacked them, intent on stopping Celosia and Clem from "damaging time and space beyond repair". He was responsible for Theron losing her eye, and Celosia sacrificed herself to allow Clem the time she needed to escape back to the past.
Mige visited this future twice, once on Sept. 14, 2024, and the other sometime in early 2036.

Timeline-002

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This timeline is one of the darker futures that Mige saw. After Crystal's death in 2020, Mige blamed himself and went into seclusion. He eventually took Clem and cut everyone else off, intent on moving to Kanto. Alexa tracked him down fairly quickly and ended up staying with him in Saffron City, where the two would start a relationship.
However, cutting his friends out of his life didn't protect them. Celosia lost her mind upon Lysandre's death, becoming a twisted and corrupted version of herself that would eventually usurp leadership of 'Team Riot'. Zoey, Bill, Sycamore, Ami, and more people died, many at the hands of either Vincent or Celosia. Upon the deaths of Jenn and Felicity, Aerik Hargraves tracked Mige down, as he blamed their deaths on his inability to stop Celosia. Mige broke both of Aerik's legs using his aura capabilities.
At some point in 2023, Mige and Alexa had a son they named Aubrey. Over time, Mige became more obsessed with finding and stopping both Vincent and Celosia, becoming a brutal and hardened vigilante in the process. This drove a rift between Mige and Clem. Alexa would break off their engagement in 2026 due to Mige's obsession.
By February 2029, Mige had almost nobody left and nothing in his life but "the mission". Alexa, despite having broken up with him, apparently still tries to keep in touch as she showed up to Mige's apartment in the hopes of getting him to call Clem for her birthday.

Timeline-003

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The first timeline Mige traveled to past the Inflection Point. In this future, Mige and Crystal are married with Clem and three biological children: Leon and Casey (twins), and Lydia. In this future, the world is still devastated by Team Relic, and while things are bad they don't seem as dire (though admittedly, Mige does not know much of the world in this timeline). The Organization is still a fairly large problem, as is Vincent; Mige has still lost many friends in this future, including Jenn, Lara, Bill, and others. This future is another where Celosia lost her mind, though she acts as a lone agent.
Not much is known about this future, except that Crystal no longer models professionally and has a career related to Pokemon battling; Mige is somehow famous or well-known; Kai married Valerie and they had two sons, but they are going through a messy divorce at the same time as Kai and Marcellus' restaurant is going out of business, driving Kai to move in with Mige & Crystal and sleep on their couch.

Timeline-004

Main article: Timeline-004
In this future, the group stopped Team Relic before they could commit the "ecological disaster", but they still caused fairly widespread devastation. Mige and his friends were so worried about the Organization that they were unable to stop Team Relic before the last minute. Many of Mige's friends died in the process, including Crystal, Jenn, Lara, Tim, Aliana, Sycamore and Viola. Notably, this is the only timeline in which Bill is alive.
Mige and Alexa are married in this timeline, with two biological children in addition to Clem: Aubrey and Mia. While Aubrey does not seem to have inherited any aura-based abilities (though he is apparently quite good with computers), Mia is both an aura guardian and a traveler, like her father.

Timeline-005

Main article: Timeline-005
This timeline seems to be quite similar to Timeline-001, with some major differences. Even more people are dead in this timeline, and while Team Relic doesn't seem to have devastated the ecosystem the same, Clem and Celosia both still imply that the world outside of cities is "dangerous".
In this timeline, it is implied that Mige and Crystal were together for some time before she was killed (implied to have been killed by Vincent). This seems to have caused Mige to gain a great deal of motivation to stop their enemies, but Mige also doesn't seem to have been able to deal with Crystal's death and emotionally shut himself off from everyone by Clem.
As of 2024, Mige lived in an apartment with Celosia and Clem, only in this timeline Mige and Celosia did not have a son and were not together. The two would eventually get together, thanks to intervention from Mige-Prime, and eventually had two children (Bill and Persephone).
In 2033, Will Darrow killed Celosia to keep her from "destroying time". After Celosia's death, Mige was once again unable to deal with things and disappeared, leaving his children with Professor Sycamore. Allegedly he left to "deal with Will" but he never returned. By 2043, Mige was living alone in a trailer park in Johto, where he was found by Clem.

Timeline-006

Main article: Timeline-006
In this timeline, things seem to go very bad for everyone. As of 2027, most of Mige's friends are dead, and he is living in an apartment with Tim in Cerulean City. Tim and Zoey broke up long ago, which forced Tim to find Mige in Kalos and travel with him. By that time, Crystal, Lara, and others were dead. It's implied that Mige and Jenn may have been in a relationship, though this isn't verified. At one point, Jenn is killed by Will Darrow. While Henri was able to bring her body back to life, her mind is gone. Mige spends much of his money for Jenn to live in a nice mental hospital. Mige can no longer use aura abilities, due to taking medications that cut off that part of his brain.
Mige's life in this timeline consists of drinking every night with Tim, Tim's girlfriend Nikki, and their friend Kori, or Korrina, who Tim is pretty sure has a crush on Mige. Mige dated Alexa for at least a little while in this timeline, though she left him due to him "losing himself and giving up".

Timeline-007

Main article: Timeline-007
In this future, Mige is married to Lara and they have four biological children: Augustine and Alice (twins), Marcellus, and Naoko. Both August and Alice have aura, with August being a Channeler and Alice being an Aura Guardian.
In this timeline, when Clem begins her training journey in 2024, she leaves with her childhood friend Roy. The two would travel together for some time and, by 2033, the two are engaged.
In this future, Team Relic seems to have been dealt with for the most part, with the Organization and Team Eclipse being larger issues (among others Lara only hinted at). Many of Mige's friends are dead, unfortunately, including Crystal, Jenn, Celosia, and others.
In 2036, it is revealed that Alice is a Traveler like her father.

Timeline-008

Main article: Timeline-008
This timeline seems to be nearly identical to Timeline-007, with some minor details changed. It can be safely assumed that much of what is canon in Timeline-007 also applied here, at least broadly speaking. These details include Naoko's name changing to Yuki.
Mige visited this timeline in early 2044. Mige and his family live in a house somewhere in northern Sinnoh "due to the calamity". Lara is sick, with the same disease she was diagnosed with originally. This is because of Vincent, who was able to use his aura to "undo" Lara's recovery and make her sick again. She is terminal and nearing death, which caused both Marcellus and Yuki to return home, though it is mentioned that August still lives at home to help take care of his mother.
Alice seems to have lost her mind, due to Traveling and swapping bodies with many others of Mige's future daughters. She is in a "very comfortable" hospital, which she escapes from time to time.

Timeline-009

Main article: Timeline-009
In this timeline, Mige has lost everything after going temporarily to the dark side, where he and Celosia wreaked considerable havoc over the course of a year--and had a daughter named Morgan, who was being raised by Professor Sycamore. Mige was only saved by Jenn, whose death at Celosia's hand snapped Mige out of it.
Now, Mige is a penniless drunk living in Ryan Fairchild's basement. Mige has expressed that this is the worst timeline he'd ever encountered.

Timeline-010

Main article: Timeline-010
Mige found this timeline in 2024, where he, Clem, and Mabel lived in the apartment in Lumiose City. Mige saved Mabel and the others from Celosia. After everything was done, and after losing almost everyone, Mabel volunteered to move in and help Mige with Clem.
As of 2024, Mige and Mabel were together (though Mige was reluctant to label their relationship, as he was worried that might draw Vincent's attention) and Mabel was four months pregnant with their child.
In this timeline, Louis became a sort of mad-scientist pirate after losing Garnet, Charlie, Jenn, and others.

Timeline-011

Main article: Timeline-011
In this timeline, Mige is married to Crystal with the twins, Leon & Casey, and their younger sister and possible Traveler Lydia. In this timeline, Vincent causes a great deal of harm and destruction here, as well, as does Will Darrow. But things aren't all bad, as Bill is alive and fewer people are dead overall. Bill lives as a hermit in Cape Cerulean after "what happened with Louis and his operation".
Mige is the National Professor of Kalos, and Crystal makes a point to tell Mige where Lydia's bedroom will be.

Timeline-012

Main article: Timeline-012
This timeline is extremely similar to Timeline-001, with differences both major and minor. Many people are dead, but the causes seem to be different. Mige and Celosia are together with a baby son named Bill. Clem, Celosia, and Wyatt (Clem's friend) celebrate Mige's birthday with him.
In this timeline, Alexa exploded, Jenn never came back after leaving with Bill, and Amanita's skeleton exploded (?) but they were able to stop Team Relic before an ecological disaster.

Timeline-013

Main article: Timeline-013
This timeline is the first where Jenn is alive, and she is married to Mige. They have two children, Willow and Tim, and live in Aspertia City. Jenn is the Unova National Professor and Clem is Master Champion of Kanto/Johto. Kia is the gym leader of Aspertia City, and Bill is also alive and living in Cape Cerulean.
Jenn also tells Mige that Crystal and Theron both die in the "upcoming Inflection Point" in Avignon Town, and Lysandre becomes a criminal. Mabel, Celosia, Aliana, and Bryony all seem to fall into darkness with him, following him with a fervor that Jenn describes as "borderline religious".
Unfortunately, this timeline ends in tragedy as a yet-unexplained third daughter named Selene appeared and vanished with Willow before Vincent appeared, murdering at least Jenn and Mige's son, Tim before Alice was able to get them out of that timeline.
Mige traveled to this future with Alice. Notably, this timeline marks the first time Mige has ever physically traveled to a timeline, as opposed to his usual method of Traveling, thanks to Alice.