I watched this before the Fate/Stay Night: Unlimited Blade Works TV Series. I also watched it again have watched its sequel. So I watched it twice, both seasons of Fate/Zero and not I am writing a review on both seasons of Fate/Zero here.
Story: 10/10
Based on a Light Novel series this time and NOT a visual novel as is it's sequel anime, this particular story does NOT have different routes so it's story is absolute and unchanging depending on choices made. This is the prequel to the events that occurred in Fate/Stay Night and it did an excellent job on connecting and further developing on the characters that survived and returned in the sequel.
ART: 10/10
This was created much before ufotable's Unlimited Bladeworks so it's quite obvious it wont be the same as it but it is still excellent!
Sound: 10/10
Another great soundtrack, I had to get them all!
Character: 10/10
Excellent character development, for each from the inspiring rider, the arrogant archer, the deranged caster, the honorable lancer, the furious berserker and sad, confused saber (LOL). I have to say that the rider of this story is one of the most inspiring servants I've ever seen in this franchise. I swear Gilgamesh is an extremely over-powered servant.
Enjoyment: 10/10
I laughed, I worried, I had tears welling up in my eyes, I was inspired, I came to understand, I empathized, I resented, I enjoyed. Great anime creation. Overall 10/10