Lancer (Fate/stay night)

Lancer is a fierce, but balanced warrior who enjoys combating a worthy opponent. He has a playful attitude and takes a very carefree approach to life, but is quick to work himself into a frenzy during a heated battle. Lancers are hailed as the "Most Agile" of Servant classes.

Identity
Lancer is , a hero from the Ulster Cycle of Irish mythology. He is a demigod, the offspring of a mortal woman,, and the deity,. Although born with the name Sétanta, he adopted Cú Chulainn after killing the hound of a smith,, and promising to replace the slain canine while another was reared. Cú is the Irish Gaelic word for "hound." During Cú Chulainn's expedition to the Land of Shadows in Scotland, he trained under a sorceress named Scáthach and acquired his signature weapon, the cursed javelin, Gáe Bolg.

With his heroic exploits, Cú Chulainn acquired a reputation of savagery in battle, though he was a well-meaning and courageous young man. However, above all, he is best known for keeping his word. He once tells Shirou that he also could have been summoned as a Berserker class because of his savagery. His Noble Phantasm is Gáe Bolg, a cursed lance that inflicts wounds that do not heal. When its name is called, it reverses cause and effect to strike the opponent's heart without fail. The proper use is as a throwing weapon and has such piercing power that it has only been stopped, at great cost, by Archer utilizing Rho Aias.

Role
Lancer was originally summoned by Bazett Fraga McRemitz, an Irish representative of the Mage's Association. However, Kotomine Kirei murdered Bazett and severed her left arm to obtain her Command Spell. He then used her stolen Command Seals to gain the allegiance of Lancer and enter into the 5th Holy Grail War. Despite his wishes to avenge his fallen master, Lancer was forced to bend to Kotomine's will. Lancer is disgruntled at having to serve a Master who uses such cowardly tactics, but he is forced to obey Kirei's wishes.

Kirei chooses to employ a passive strategy regarding Lancer. He has Lancer go out on reconnaissance, and scout the locations and identies of other Masters and gauge how dangerous their Servants are. During his fight with Archer, Lancer noticed that Emiya Shirou had witnessed his entire battle. Believing Shirou to be an ordinary human, to preserve the secrecy of the Holy Grail War, Lancer silences Shirou by stabbing him through his heart.

Later, Lancer realizes that Shirou has recovered from his mortal wound, so he tracks and corners the young mage within the shed of his home estate. Before Lancer is able to strike a mortal blow, Shirou is rescued by the recently summoned Servant, Saber, who then engages Lancer in combat. Outmatched, Lancer flees the scene just before the arrival of Archer and his master.

After this, for the majority of the story, Lancer is generally inactive.

In Fate, Shirou is lured to Kotomine's church, and once again wounded by Lancer. Saber eventually arrives to rescue Shirou. After events unfold, Kotomine reveals his other Servant, Gilgamesh, the Archer from the previous war. Kotomine orders the both of them to kill Saber and Shirou, and leaves. Lancer, disgusted by Kotomine keeping Gilgamesh's existence a secret from him, and by Gilgamesh himself, decides to rebel against Kirei. Though he claims he's doing it out of hatred for Gilgamesh and Kotomine, and not to help them, Lancer chooses to fight Gilgamesh and thereby aids Shirou and Saber in escaping. He is then defeated by Gilgamesh.

In Unlimited Blade Works, after being driven out of his church by Caster, and faking his death, Kotomine orders Lancer to ally with Shirou and Rin. Lancer helps them with their plan to defeat Caster by fighting Archer to distract him, so that Rin and Shirou are able to enter the church. Ostensibly defeating Archer, but choosing not to conclude their battle, he later reappears to offer his aid again to Shirou and Saber after Rin is captured. Upon rescuing Rin, Kirei suddenly appears and orders Lancer to kill Rin. In addition to his previous disgust with Kotomine, Lancer has come to admire Rin, and therefore refuses his order. In response to this, Kotomine uses a Command Seal to force Lancer to give himself a mortal wound. However, before he fades away, Lancer manages to kill Kotomine, and bids goodbye to Rin. Before his death, he sets the Einzbern castle on fire.

In Heaven's Feel, upon sensing a disturbance at the Ryudou Temple, Lancer investigates it as per his orders by Kotomine to scout the competition. He discovers and engages in battle with True Assassin, but during the battle, he is attacked and killed; then absorbed by the black shadow of Avenger.

In Fate/hollow ataraxia, Lancer's role is expanded far beyond Fate/stay night. He is normally spotted fishing at the Fuyuki docks, but he is frequently seen wandering the city or at his part-time job as a grocer. He is quite amiable, chatting with many of the former Holy Grail War participants, and is well liked. He makes no attempt to combat the Shadow Wolf Beasts during the Fuyuki eclipse, instead quietly presiding over Avenger's ascent into Heaven's Feel from a distance.

Abilities
Lancer's weapon, the Gáe Bolg, a cursed spear which is said to inflict wounds that do not heal as long as the spear remains in the world. His weapon itself has two main techniques which can be classified as separate Noble Phantasms.

The first technique is to reverse causality in a technique called the The Spear of Impaling Barbed Death which can be explained by saying the cause is that "the heart is pierced" and the effect is that "the spear is thrust". Thus, the lance has already hit the heart before it is thrust, and the actual action is merely a formality that occurs due to the piercing of the enemy's heart.

The second technique utilizes the full potential of Gáe Bolg's curse by converting prana into energy and releasing the accumulated power after the spear is hurled, detonating on impact with enough power to blow away a multitude of enemies.

If he were to be summoned in Ireland, he would have had potential access to a castle, chariot, protection of sleeplessness, and the like due to being in the land where his legend took place.