Disclaimer: I do not own anything from the Naruto universe, or else the Sharingan wouldn't be a mess of OP crap, and I do not own anything from the Fate universe, or else I would never have made any of the weird stuff with aliens and just focused on more historical characters turned into cute girls.
Authors Note: I love just about any crossover that involves Naruto being summoned/sent into different series, with the Fate universe providing a super convenient excuse to summon Naruto. Additionally, I have read just about every Naruto/Fate crossover on this site that's above 40k words, so if you recognize something from a different story, odds are I took inspirations, so I am gonna credit all Naruto/Fate story for inspiration, most notably the "Unlikely Berserker", "Unlikely Caster", and "Lucid Berserker" stories.
Several points before I start my story.
1. My Naruto as a servant is gonna be completely overpowered and I will ignore any stupid flaming or complaining in the reviews. While it won't be something edgy or stupid like "Rinnegan-Sharingan/Mokuton super edgy 'you are already dead' with super special finger-less gloves (why fanfic writers always give their edgy OP main characters those is beyond me), Naruto will not really lose fights. I won't have him simply walk up to Lancer or Gilgamesh and one-shot them, he will most likely win handily, and will have blatantly strong stats and multiple Noble Phantasms, because within the Naruto universe he is basically a god.
2. My knowledge on the Naruto series is much greater than Fate, especially Fate/Zero. While I recently watched most of the series again, mostly because I love Rider as a character and all of his scenes, my knowledge is much better for Fate/stay night so if I make a small plot point mistake just let me know in the reviews in a calm and reasonable manner. Any review that looks like "hurr durr Lancer is weak that's not how he fights" or "hurr durr Naruto is broken that's trash" I will completely ignore. I am gonna use the knowledge on the Fate wiki, as well as based on the copies of the script online to base certain scenes (such as the banquet of kings) to write certain parts,but bear with me if I screw up something with the Fate lore and let me know, especially to describe histories of Servants and their noble phantasms.
3. Furthermore, I will be slightly deviating from canon pretty much from the start (duh with Naruto being summoned), and it will most likely expand from there. If you don't like it, tough shit. One of my biggest gripes with fanfiction writers is that they introduce new elements, whether it is a crossover or new powers, and then never change anything from canon. Naruto will be fucking shit up in this story, and if you don't like it, I don't care. Some characters may end up being out of character to you and you want to complain, I don't care. Naruto has an effect on the people around him. Deal with it.
4. This is my first real fanfiction story that I have ever published, previously the only things I wrote were tiny one-shots that were less than 1k words. I have read dozens of stories on this site, so I understand how stories with super interesting concepts and ideas can be ruined by poor grammar, so I will do my best. Stating this, don't complain in the reviews, just point it out to me and I will do my best.
5. I already do have another idea for a crossover, which probably will be a Fate/Highschool DxD story with Shirou, Naruto/Highschool DxD, or maybe Fate/Konosuba story, because I think that the DxD universe has a lot of potential that is ruined by harem antics of a perverted Issei and could fit Shirou/Naruto in nicely, while the Konosuba story has a lot of potential for a more comedy based story with most likely Shirou and some combination of characters getting up to crazy shenanigans. These will take inspirations from the top fanfiction stories like "A Demon Lords Hero", so if you have any good ideas PM me or leave it in the reviews.
With that said, this will be a work in progress. I am not 100 percent on how I want this story to resolve, so if you have ideas leave it in the reviews or PM me. I will try and update consistently, I usually work 7-3ish during the week so expect updates. Enjoy!