Watch the prequel of Fate/Stay Night, Fate/Zero. It's 100x
better.

Actually anyone who wants a beautiful and very well done action anime should watch Fate/Zero. Fate/Zero has just amazing action scenes compared to F/SN and everything is just done with alot more quality.

Fate/Zero is mainly about 7 Mages who compete in a war for the holy grail which can grant any wish. Each mage summons a servant who is a legend in the past, from king Auther to Alexander the Great and other heros. Each servant is placed under the category Saber, Archer, Lancer, Rider, Caster, Berserker and Assassin, making each servent use a different style of fighting to kill each other in a tag team battle with their masters.

What makes Fate/Zero more unique than other action series imo is thair characters. Each character was different and unique compared to one another, and weren't all highschool students like F/SN.
The focus on the characters got me hooked, they never focus on soley the main character, heck the main character only had slightly more focus compared to all the other characters. They built a bond between each character and how they each interact with one another, viewing all their goals and personality, givingeach character tons of character development.

The only downsides to Fate/Zero which otherwise would've been one of those "Master Piece" is that they spent 40 minutes of the first episode explaining what is going on. The first episode is boring but crucial to the story and it's worth watching it to see the epicness of the rest of the series.
The other downside is that because Fate/Zero was released after F/SN, they had to adjust the series to match what happens in F/SN, which really lowered the quality of the series at only one point.