War of the Holy Grail—Pursuing the power of the "Holy Grail" which grants a miracle, this is a contest in which seven magi summon seven Heroic Spirits to compete for it. In that battle whose conclusion was postponed three times, now, the fourth war commenced again. Entrusting their dearest wish of victory, the magi joined the battleground called "Fuyuki," but amongst them, there was a man who was always alone, and could not find out the meaning behind his fights. His name was Kotomine Kirei. Not comprehending the guidance of fate, Kirei was lost, and had kept questioning. Why someone like his was given the Command Seals. However, the fate of his fights crossed Kirei's path with a nemesis by chance. That person is—Emiya Kiritsugu. A man who was sterner than anyone else, more merciless than anyone else, and who sought the miracle of the Holy Grail.

Merely recited in fragments in Fate/stay night, this is the Fourth War of the Holy Grail 10 years ago. The truth which unfolded behind the battle between Shirou's foster father, Rin's father, and the younger Kotomine Kirei, is finally revealed...

(Source: Baka-Tsuki)

A crossover manga of Fate/Stay Night and Magical Girl Lyrical Nanoha A's.

Melty Blood: Rojiura Nightmare is a spin-off and sequel to the Melty Blood fighting games and manga, as well as the Fate/Grand Order mobile game.

The story takes place in an ordinary Japanese town, Fuyuki City. Hidden from society, there has been a deadly war going on in this town. Seven sorcerers known as "Masters" summon powerful familiars called "Servants," and they all fight each other till the last one. The last one is said to attain the Holy Grail, which will grant them a wish. Only a few know when this War started and what the Holy Grail is, but the war is about to begin again this year.

The main character is Emiya Shirou, who lost his parents in a fire and was adopted by a man who called himself a sorcerer. Admiring his stepfather, he has been training himself to be a sorcerer. However, he had no talent and he could barely use even one type of sorcery. His stepfather has already passed away, and today he's a sorcerer without any skills or knowledge. He is involved in the War of the Holy Grail when he accidentally summons Saber, who is said to be the strongest servant of all...

Heaven's Feel is one of the routes in Fate/stay night. The heroine of this route is Sakura Matou.

A 4koma manga

When Lord El-Melloi II, the later Waver Velvet, gets asked to claim his inheritance over Adra Castle, he travels there with his apprentice Gray to do so. But they are not the only ones called that way. The will of the previous owner states that the assembled contestants—including Luviagelita Edelfelt—must compete in a game of wits to win the castle.

Melty Blood (メルティブラッド, Meruti Buraddo?), is a visual novel and fighting game, co-developed by dōjin circles Type-Moon and French-Bread, originally released at Comiket on December 2002. It is shortened as simply Merubura (メルブラ?).

Based on Type-Moon's visual novel game, Tsukihime, it later spawned an arcade version, titled Act Cadenza, that was developed by Ecole Software and has also been ported to the PlayStation 2. Act Cadenza is the first Type-Moon title to receive a PlayStation 2 port.

A manga version by Takeru Kirishima has been serialized in Kadokawa Shoten's Comp Ace.

[from wikipedia]

A manga which helps you learn about Fate/Grand Order!(Source: MangaDex)

The story takes place in approximately the year 3000, when humankind arrived at the peak of its civilization, but is loosing it's will to keep living. It follows a girl, called "princess" by those around her, living on a small island with a fifty person colony and a shinning coral reef. She is descendent of Moon people, and it focuses upon how her ancestor supposedly came to Earth.

The plot centers around a Grail War faultily copied from the Third Holy Grail War in Fuyuki. After the end of the third Grail War, an organization from the United States that has magi separate from the London-based Mage Association as members took data from Fuyuki's Grail War and planned their own ritual. After seventy years, they used the city Snowfield as the Sacred Land for their own Grail War. They were unable to successfully copy every aspect of the ritual, which lead to it acting only as an imitation that has lost the Saber class and allowed for the summoning of strange Servants due to the definition of a "hero" being blurred.

(Source: Type-Moon Wikia)

The story follows Tohno Shiki, a teenage boy who, after a near-fatal accident in his childhood, gained the mysterious power to perceive lines covering everything around him. When he cuts along these lines, whatever it was immediately falls apart with a clean cut; in other words, killing it. He would have quickly gone insane from living in a world that could fall apart so easily, had it not been for a wandering self-proclaimed magician who gave him a pair of glasses that blocked his unnatural perception when worn.

Soon afterwards, he was disinherited from his family and sent to live with some relatives. For eight years he lived a normal life, hiding his special eyes, until one day he receives a letter inviting him to come back home. Shiki suddenly becomes caught up in strange and life-threatening series of events, ones that are somehow linked to his childhood accident and a forgotten past...