Summary
One of the fun things about every mainlineElder Scrollsgame is the opportunity it gives the player to occupy the role ofa legendary hero. FromThe Elder Scrolls: Arena,wherein the player takes control of the Eternal Champion, toThe Elder Scrolls V: Skyrim,featuring the Last Dragonborn, each hero is faced with a unique set of challenges that only they can overcome.
One interesting question, however, is what happened to these figures after each game? While what exactly happened to these characters is a mystery to some extent, there are a few important details in the canon that do well to indicate what became of each mainlineElder Scrollshero.

The Eternal Champion has very little information available on what became of them after the events ofThe Elder Scrolls: Arena. What is known about them is that, canonically, their name is Talin, and they are indicated to be male (even though the game allows players to customize their gender).
At the end of the game, the Eternal Champion takes their place at the emperor’s side after freeing him from evil sorcerer Jager Tharn’s Oblivion prison, seeing to the needs of the Empire. Unfortunately, the Eternal Champion is never heard from, or mentioned, in any other mainlineElder Scrollsgame, though his emperor,Uriel Septim VIIis seen inDaggerfallandOblivion.

Daggerfallis, to this day,one of the most massive RPGs ever made(and was even remade somewhat recently). The player character has so many paths to take, so many stories to experience in the setting of Illiac Bay that any canon interpretation of their fate would have a difficult time pleasing everyone.
That said, the game actually has several canon endings that exist simultaneously thanks to the “Warp in West.” This means that any number of things could’ve happened to The Agent after the events ofDaggerfall,and all of them are legitimate. One thing that is consistent across each ending, however, is that contact with The Agent was lost. One ending results in their death in Aetherius, while the others imply that they lived, though nobody knows what truly happened to them.

The Nerevarineis one of the more popular player characters among fans of theElder Scrollsgames, and is, to some degree, the subject of widely circulated fan fiction by formerBethesda Game Studioswriter, Michael Kirkbride. The Nerevarine is the reincarnation of Indoril Nerevar, prophesied to unite the province of Morrowind and destroy the corrupted Tribunal.After defeating Dagoth Ur, the Nerevarine is said to have gone on an expedition to Akavir, a continent lying eastward of Tamriel and populated by exotic beasts not seen anywhere else on Nirn.
Whether the Nerevarine ever returns is determined by how much stock one puts into Kirkbride’sC0da, which posits that true canon isn’t real when dealing with fiction. InC0da, Nerevar is reincarnated once more in the Fifth era after Nirn has been destroyed upon the return of the Numidium. Many will likely disregard the idea that this is legitimate, even if it was written by a former Bethesda employee.

In terms of accomplishments, theHero of Kvatchranks among the greatest of all the mainline protagonists ofTES. Canonically, the Hero of Kvatch mantlesthe God of Insanity, Sheogorath, meaning that the player character ofOblivionliterally becomes the mad god outright. Mantling is a process by which a person lives in such a way that to others they become indistinguishable from a particular god. Thus, via the power of people’s faith, that person flat out becomes that god and assumes their office.
This is what happens to the Hero of Kvatch during theShivering Islesexpansion forOblivion, in which they defeat the Daedric Prince of Order, Jyggalag. The player is then directly referred to as the new Sheogorath, and based on their dialogue inSkyrim,literally ascended into godhood at some point after the events ofOblivion.

Given the recency ofSkyrim’srelease in comparison to the otherElder Scrollstitles, very little, if anything, is known about what becomes of theLast Dragonbornafter the events of their game. Some have speculated that the next game in the series will indicate that they eventually became a servant of Hermaeus Mora, and replaces Miraak inhis realm of Oblivionas his champion.
It is also possible that they will resist the temptation of the Daedric Prince of Knowledge, but go missing all the same. The trend of each player character disappearing in some way, and being unable to significantly affect the world again, is a virtual certainty, but how exactly it will come about for the Last Dragonborn ultimately has yet to be truly written.