[VN Spoilers] What actually led to Last Episode? : fatestaynight
All signs point out to the regular Shirou from the Fate route and, iirc they said that Archer is Shirou from some unknown route Yet two You mean Shirou meets Sieg and Jeanne shows herself infront of Saber right?. How did Shirou meet (7 children). From what I've heard, it took place after both Saber and Fate route Shirou had died and become spirits. Do they talk more about Archer? and did Saber really died in Fate/Stay night? green pasture, as their desire to see each other again was so strong. The "Last Episode" ending is most likely Shirou's hallucination as a result.
Because of how Nasu made it, it can also happen in the rest of the timelines.
Last episode Unlimited Blade Works good ending: In the VN if Shirou appoints love points to Saber the good ending will happen and Saber will says she stays for him. Shirou gets Saber as his servant and they live happily. The reason is that it is done as an epilogue for such ending it actually says epilogue.
Nasu has made epilogues for all 3 true endings. In the original game he did Heaven's Feel true ending epilogue.
After some time he did Fate's true ending epilogue "last episode" and recently he's made UBW's true ending epilogue an 11 page script that was handed to Ufotable in order to make the epilogue episode. It isn't questioned but I'm gonna address a few doubts the OP may have.
Will Shirou and Saber ever reunite again? - Quora
You may think that even though it's the canon epilogue written by Nasu, it is also fanservice because of how happy it is. Actually, reality is that all happy endings if you reach the end of the game are strongly criticised by the VN community as fanservice. Last episode makes a lot of sense as Fate's true ending epilogue as Nasu has created it because: When asked if Archer comes from the fate route in interviews he has denied it.
It makes perfect sense for Shirou to look for Saber and for Saber, who loves him deeply, to suffer waiting for him risking suffering for all eternity. After that they reach their happily ever after. Her attitude towards the rest of the people remains the same though. She also sacrifices her Holy Grail dream for him. The only difference between the good and true endings is that in the good ending Shirou gives love points to Saber, so she wishes to stay.
Do Emiya Shirou and Arturia ever meet again after Fate/stay night? - Anime & Manga Stack Exchange
As I said the only difference between UBW true and good endings is that in the Good ending Shirou gives points to saber.
She is entrusted by Merlin to a loyal knight, Sir Ector, who raises her as a surrogate son.
When Arturia is fifteen, King Uther dies, and with no known eligible heir to the throne, Britain enters a period of turmoil following the growing threat of invasion by the Saxons. Merlin soon approaches her, explaining that the British people will recognize her as a destined ruler if she withdraws Caliburn, a ceremonial sword embedded in a large slab of stone.
However, pulling this sword is symbolic of accepting the hardships of a monarch, and Arturia will be responsible for preserving the welfare of her people. Without hesitation, and despite her gender, she draws Caliburn and shoulders Britain's mantle of leadership.
Why Saber did't stay with Shiro?
Arturia rules Britain from her stronghold in Camelot, and earns the reputation of a just, yet distant king. Under the guidance of Merlin and with the aid of her Knights of the Round Table, she guides Britain into an era of prosperity and tranquillity.
Caliburn is destroyed, but Arturia soon acquires her holy sword, Excalibur, and Avalon, Excalibur's blessed sheath, from Vivian. While Avalon is in her possession, Arturia never ages and is immortal in battle.
Throughout her reign, Arturia is plagued by feelings of guilt and inferiority; she sacrifices her emotions for the good of Britain, yet many of her subjects become critical of her lack of humanity. Excalibur's scabbard is stolen while she repels an assault along her country's borders; when Arturia returns inland, she discovers Britain is being torn asunder by civil unrest.
Despite her valiant efforts to placate the dissent, Arturia is mortally wounded by a traitorous knight, a homunculus born of her blood named Mordred, during the Battle of Camlann. Her dying body is escorted to a holy isle by Morgan le Fay and Sir Bedivere. Arturia orders a grieving Bedivere to dispose of Excalibur by throwing it back to Vivian; in her absence, she reflects on her personal failures, regretting her life as king.
Before her last breath, she appeals to the world; in exchange for services as a Heroic Spirit, she asks to be given an opportunity to relive her life, where someone more suitable and effective would lead Britain in her stead.