Rider
Berserker
Gilgamesh
Assassin
Saber
Lancer
Archer
the pics above are some Servants from Fate/stay night
Kirei: This fight is called the Holy Grail War. It is a contest between seven Masters who use Servants. We do not wish for this tyranny to happen. It is a means to select the one suitable for the Holy Grail.
Emiya: That can't be! The Holy Grail is only a legend!
Kirei: The Holy Grail that appears in this city is quite real. One of the proofs for this is the presences of wonders such as the Servants. The Servants are beings very near to natural spirits. Legendary heroes of the past and of the present are materialized through the Holy Grail. They usually are present near their Masters as spirits, but Masters can make them materialize and fight at need.
Emiya: Ok, let's say there is a Holy Grail, there's still no reason to kill each other. If it's such a great thing, we should share it among everyone.
Kirei: That's a sound opinion, but we are not free to do so. The Holy Grail will choose people suitable for itself and will make them compete to select only one to hold it. The Holy Grail itself chooses the seven Masters and summons the Servants. This is the Holy Grail War. It is an advent ritual in which the Masters kill each other to be chosen by the Holy Grail and to acquire it.
Emiya: Even if only one is selected, there's no reason to kill the other Masters!
Tohsaka: Wait, there's no rule saying that Masters must kill each other. The Holy Grail is a spirit. Only Servants, being spirits as well, can touch it. The objective of the Holy Grail War is to remove every Servant other than your own
Emiya: Oh, so when only your Servant remains, only your Servant can touch the Holy Grail.
Tohsaka: Yes, so if you defeat the Servant, then there's no need to kill its Master.
Emiya: If that's so, you could've told me earlier. Then even if I take part in the Holy Grail War, there's no reason for you to die, right?
Kirei: Let me ask you one thing: Do you think you can defeat your own Servant? Servants are powerful. Not even servants themselves, let alone Masters, can defeat each other easily. But without Masters, Servants cannot exist on their own. Therefore, killing Masters is the most efficient method for killing Servants.
these are some dialogues from Fate/stay night
Fate/stay night rox!!! :D