The Fate anime series consists of Holy Grail Wars fought in search of an ultimate wish-granting device. To aid the wizards in this quest, heroic spirits called servants are summoned, based on legends that have existed in the past. There are few battles as simple as a straight brawl, but a minion's strength is a deciding factor in who walks away with this almighty Grail.

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With some of the strongest minions in any Fate series, like Iskander, Saber, and Gilgamesh, as well as some strangely powerful obstacles for these three Kings, you might want to know who the strongest minion is in Fate/Zero. Here's every single minion, ranked solely by their strength!
7 Murderer
Hassan of a hundred faces
The only servants of the Assassin class that can be summoned in the Fuyuki Wars are the 19 bearers of the Persian title of Old Man of the Mountain, or Hassan-i Sabbath. Among these, Hassan of the Hundred Faces is the nineteenth and final bearer of the name. Like other Assassins, Hassan of the Hundred Faces specializes in stealth and intelligence gathering, rather than direct combat.
However, while other minions of the Assassin class have ways to deal damage, such as Cursed Hand Hassan's Zabanya breaking his target's heart, Hassan of the Hundred Faces has no such ability. Instead, the Assassin can split into 100 different bodies, making the minion the best at intelligence gathering, but the worst everywhere else.
6 Lancer
Diarmuid
Lancers belong to the Three Classes of Knights. As such, they are usually one of the strongest melee fighters during the Holy Grail War, along with the Saber and the Archer. However, despite being able to keep up with Saber, Diarmuid is among the weakest Lancers we've seen in Fate. While he isn't very powerful, he more than makes up for it with his high battle IQ and cunning, as well as the potential of his Noble Phantasms.
The long red spear, Gae Dearg, is capable of overpowering all magical constructs. This gives Lancer a huge advantage over opponents stronger than him, as seen by him negating Saber's magical armor and being able to completely nullify Berserker's Noble Phantasm. He also has a shorter yellow spear with the name Gae Buidhe, a weapon that curses anyone it wounds to never recover from said wound.
5 Berserker
Lancelot
Berserker's main Noble Phantasm, Knight of Owner, can transform anything he touches into a customized Noble Phantasm. This is limited to anything that could be considered a weapon. In Fate/Zero, we saw him using modern machinery like guns, missiles, and even a fighter plane as weapons.

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While less interesting than other special abilities, this simple ability allows Berserker to keep up with Gilgamesh's Gate of Babylon by grabbing the weapons he fired, transforming them into his own weapons, and reflecting the incoming barrage. Furthermore, although the Mad Enhancement ability usually causes the user to lose dexterity and skill in battle, Lancelot can move instinctively, almost completely negating the drawback.
4 Caster
Gilles De Rais
During his lifetime, Gilles De Raise was completely infatuated with Jean d'Arc, so much so that he became a devout worshiper of God, believing that Jean was a miracle of divine origin. He aided her in numerous wars during the Crusades, both monetarily and as a knight; however, when Jean was eventually executed for heresy, he began to doubt the existence of God.
Gilles De Raise began committing heinous crimes: kidnapping, killing, and abusing children, all so that God could prove his existence by punishing him and could justify all the lives he had taken in the name of God. However, this judgment never came, and so this maniacal Enchanter exists.
Although he is considered among the weakest of spellcasters in terms of combat ability, his Noble Phantasm, the Book of Spells of Prelates, allows him to instantly replenish all the mana he expends. This allows him to create an endless supply of monsters, becoming a strong enough threat that even Saber, Lancer, and Rider can't easily deal with.
3 Saber
Artoria Pendragon
Based on King Arthur, Artoria is a king among kings. Completely foolproof, free of any imperfections. He was a selfless king who wanted only the best for his people. However, it was this supreme and inhumanly compassionate character that caused her people to alienate her, ultimately leading to her being betrayed and killed.
The Saber class is said to be the strongest of the seven main classes. Among the various heroes that can be summoned in the said class, Artoria is the strongest. She is unbeatable as a swordsman and knight and is made even more terrifying by her ability to hide the length and nature of her sword. Not only that, he also possesses the legendary sword Excalibur, capable of destroying hordes of enemies effortlessly with a single blow.
2 Knight
Iskander
The Servant Rider is based on Alexander the Great, the king of conquerors; during his lifetime, he created the greatest kingdom to date, placing himself in history as one of the greatest kings to ever exist. He desired to dominate the entire world and see its end, but his life abandoned him before he could do so, and his kingdom fell into ruin almost immediately after his departure from this world. As a servant, Iskander was as great as his living self, and even though the Knight class is usually too weak to stand up to the three knight classes in direct combat, Iskander had no trouble fighting Saber, even earning Gilgamesh's complete respect.

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His chariot, Gordius Wheel, allows him to use the Noble Phantasm called Via Expugnatio, ramming the enemy with sparks of lightning. However, this is only one feature of Iskander's true power. Iskander's true Noble Phantasm is Ionioi Hetairoi, a Reality Marble that allows him to summon tens of thousands of heroic spirits who have served under him in his life. This is Iskander's trump card and is said to be potentially as strong as Gilgamesh's Gate of Babylon.
1 Archer
Gilgamesh
The Noble Phantasm of the King of Heroes is called Gate of Babylon, the single strongest Noble Phantasm of any minion in Fate. It allows Gilgamesh to summon and rain down upon his enemies an endless supply of weapons from his hoard. These weapons include Noble Ghosts belonging to other heroic spirits.
While he normally uses weapons as simple projectiles to send, he can still use Ghosts to their fullest potential, as seen by him using Enkidu to keep Heracles in check in Fate/Stay Night. If you piss him off, Gilgamesh has access to Enuma Eilish (EA), a Noble Phantasm capable of obliterating reality itself, with no way to defend himself against it.

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