Kayneth El-Melloi Archibald

Kayneth El-Melloi Archibald is an antagonist in the light novel and anime series Fate/Zero. He is a wealthy nobleman who is descended from a long line of magi (not unlike the Einzberns, Tohsakas and Matous) and one of the seven Masters in the Fourth Holy Grail War. He is the Master of Lancer and the fiance of Sol-Ui Nuada-Re Sophia-Ri. He is also a former teacher of Waver Velvet, and is indirectly responsible for him entering the war.

He is voiced by Takumi Yamazaki in the Japanese version of the anime and Doug Erholtz in the English version, the latter of whom also voices Gin Ichimaru.

About
As a highly talented magus who has had almost no hardships in life and comes from an ancient magical lineage that goes back nine generations. As such, he is extremely full of himself, and holds a great amount of hatred towards anyone who wrongs him, wishing to torture and kill them if at all possible. He is also a complete coward, preferring to stay out of sight while his Servant Lancer does the fighting. He is introduced by publicly humiliating Waver Velvet by deeming his theory that new mages can increase one's potential through effort and experience which would allow them to overcome the handicap of being generations behind (while Waver would later conclude that he was right, it still doesn't excuse his actions). He also constantly belittle his Servant due to the latter's chivalrous nature, not unlike Kiritsugu Emiya's own treatment of Saber (though in his case he just ignores her).

The closest thing to a redeeming quality he has is his genuine love for his fiance Sol-Ui, which she does not return. This is shown when she gets held hostage by Maiya Hisau, and he agrees to his terms that the two of them will not be harmed as long as he makes his Servant kill himself, unaware that it's a trap. However, he refuses to hand over his Command Seals to her after being critically injured, since he was convinced that Lancer was hiding something from him when he said he had no desire for the Grail, not being able to believe that he really has no goal beyond serving his Master with honour.

All in all, Kayneth acts as a foil/evil counterpart to Waver; both are arrogant, cowardly, highly intelligent magi who desire the Grail for selfish reasons. However, Waver's arrogance is actually a facade to hide his deep-rooted insecurities and, despite panicking easily, he chooses to stand on the front lines with Rider. Kayneth, on the other hand, chooses to operate from the shadows while allowing Lancer to do the fighting (a trait that causes Rider to deem him unworthy of being his Master) and is just as arrogant as he makes himself out to be, believing his victory of the Grail to be a foregone conclusion. Additionally, Waver eventually grows to realises that he never needed the Grail and gets the happiest ending of all the Masters (i.e. he's the only one to come out of the war better off than he was before it), while Kayneth doesn't learn from any of his mistakes until it's too late and goes out more disgracefully than any other Master (this includes Ryuunosuke Uryuu, who, despite being a psychotic serial killer, accepts his death with dignity and ultimately got everything he wanted).