Okay, I know I've +1'd it already, but Bloble's Tomb of the Sun God is too awesome to not merit more.
It has the initial toughness to overcome of being completely about original characters, but Bloble wastes no time getting the reader oriented with the Scribe, the main character himself, and who he is - while at the same time effortlessly planting the story itself within the Nasuverse, making it seem like an only natural extension of the world of Fate/stay night as a whole.
I'll admit that it does take some time to introduce more major characters, and this puts perhaps too much strain on the main character's ability to hold interest; however, once more characters are slid into the plot, both major and minor, the narrative really starts coming alive, and Bloble seems to have no problems whatsoever managing each character as their own unique entity in the narrative. Each character comes into the story at an appropriate time, and the interactions between the people that make up the story is fantastic. I'll reiterate this: every character is unique and full of their own zest and, well, character, and at no point does the cast or the plot seem bloated or unwieldy. Bloble wields his characters well as agents of the plot and organic and intriguing people, knowing what each should say in any given situation, which all adds up to make them feel especially real and relatable.
That might make you think that the story could see things start to decay in cases where there aren't a whole lot of characters to interact, but especially in recent chapters, Bloble shows that just isn't true. Even with just the power of the protagonist's inner monologue and the narrative itself, Bloble keeps the reader's interest in an intense and enjoyable reading experience that consistently makes you want to see what happens next. It's easily one of those stories I can't wait to see more of, and its generally great storytelling is at the same time approachable and appreciable. It doesn't pander to a stereotypical fanfic audience, and has professionally appreciable prose all around. His characters' conversations are clever and interesting yet easy to follow nonetheless, and his action is as intense and vivid and thrilling as any film. Extra attention, in fact, can be given to the style of action adventure Bloble uses; it's an interesting mix of a character piece and classic, subtly Lovecraftian horror, except without cluttered, overtly verbose prose to weigh it down. He emphasizes and capitalizes on the kind of fear of the unknown, the idea of powerlessness, that ultimately defined Lovecraft's work, but with genuine sympathy for the protagonists and an honest curiosity, every step of the way, as to whether they'll survive... or not.
All in all, Tomb of the Sun God is a knockout piece of fiction, and I'll always want Bloble to write more of it. I would buy Ziploc bags of Tomb of the Sun God and escape into a darkened alley, just to slowly smoke it to get my fix. And all that would be seen as the spark of my lighter ignited the fresh, herbal prose of Tomb of the Sun God would be my face, my eyes transfixed as I contemplate what might happen next.
This is the best addiction you can have, as far as stories go. If you have any spare time, go ahead and catch up, read Tomb of the Sun God, and I assure you, this is something you won't regret.