First of all, you have to understand that Steins;Gate is completely unique compared to other anime, in terms of story line. Now, with such a complex plot, it would be incredibly easy to mess the series up. Except that they didn't. If they did, it wouldn't a masterpiece. Steins;Gate explores the world of time travelling and time lines, putting in acknowledgements to theories such as the butterfly effect and how, once you change a minor thing of the past, the future transitions into one large scrambled egg. Once you pass the first slow starting episodes, the intrigue and mystery begins, and the pace of the series accelerates. The plot throws in numerous surprises and sudden, unexpected turns that, in turn, creates a powerful ending that is almost flawless. Also, you're hit bluntly in the face with quite a lot of feels early on in the series.
One of the great things about Steins;Gate is that the characters are developed incredibly well. Astonishingly well. To the point that you feel connected with them in terms of their feelings and aims. They each have their quirky side too - not everything is all serious. I'm talking about the mad scientist personality, the Dr.Pepper jokes and Daru's perverted jokes which lightens up the series so that it isn't all serious drama. But the trouble is, the more like able the characters are, the harder you find it to leave them behind when the series ends, meaning that even a week after Steins;Gate ends, you'll probably still be thinking about Okabe whenever you spot a bottle of Dr.Pepper.
I didn't really pay attention much to the soundtrack of the series, i admit, due to the fact that i didn't find it all that enthralling or unique. However, i did enjoy the opening and the ending particularly. Aside from that, the soundtrack did it's job of emphasizing the mood/atmosphere of scenes pretty well.
The animation in itself was done really well though - i found that the consistency was great, meaning that (to my eye) there was no sudden drops in quality.
Something that i loved the most was that the ending was fantastic. There were barely any loose threads, and as a poor ending can sometimes ruin a good series, i'm grateful that they executed such a content finale.
I stress that you must watch this series. It's not enough for you to read however many reviews you can lay your eyes on, but to actually experience this masterpiece for yourself.
El Psy Congroo.
