Story: 9/10
A story based on Japanese History, which actually entertained me and educated me a bit, mainly because I have Japanese classes. It wasn't boring, it didn't drag out that much and if it did, it would be fan-service/some comedy skit added into that. If I were to give a score on originality about the type of story being used in the anime, I'd give it a 9 but if I based it on how much it entertained me, I'd give it a solid 4 but the only thing that saved it was they made it different by putting the protagonist to be someone from the future, having the 'ability' (not sure if I could call it an ability) to see the future. The type of male protagonist that come from the future/different worlds and want to save the current world always make the anime better, personally. It had a lot of action, mainly sword fighting and a little bit of magic I suppose. There's harem and romance, but the harem slowly develops throughout the anime, which doesn't bother me but as a guy who has watched a lot of harem/romance anime, it was very predictable on who's going to fall in love with the protagonist. It was somewhat funny, mainly using perverted jokes which are alright, but if overused and repetitive, can get really annoying.
Art: 8/10
I don't know if it's just me, but the art style gave a history-ish vibe. Other than that, the colors and nice and bright, animations are smooth and is very easy to catch the eye.
Sound: 7/10
The OST fit scenes nicely and used necessary, not overused and isn't too loud. The OP fit the theme of the anime, giving that 'army' vibe (I'm probably stoned) and the ED fits the romance side of the anime.
Character: 9/10
Sagara Yoshiharu, the protagonist who comes from the future (circa 400 years). He's very obsessed with history games, mainly with the Shogunate eras and all those. He's very talented, in his own ways because he remembers a whole period of time from the past and uses it to his knowledge to try to save characters from dying. A very kind but perverted person.
Oda Nobuna, a very cheerful girl who dresses very minimal. She's a tsundere (not a flat one!!) and cares a lot for the people she loves. She's not that smart, mainly because she is easy to trap. Without Sagara her nation would've died. Kind-hearted and caring (mostly to Sagara ;))
Enjoyment: 10/10
It was a new experience for me, as not only did it entertain me, but it actually educated me. Yes there's fan-service and a lot of 'loli' characters, but hey the action was quite nice.
Overall: 9/10
If there's a second season out there, I'd watch it. I really liked the idea of this anime. If you like protagonist who comes from a different world/future and wants to save the current world he is in, then Zero no Tsukaima is for you. If you like history but not very educational, then Hyakka Ryouran might suit you. Would I re-watch this? Definitely.
