TLDR
Story – 6/10 – 6 x 0.275 = 1.65
Art – 7.5/10 – 7.5 x 0.2 = 1.5
Characters – 7/10 – 7 x 0.225 = 1.575
Enjoyment – 7/10 – 7 x 0.3 = 2.1
Total – 6.825 -> 7
Story – 6/10
Story is not Claymore's strong suit. The story is linear and often predictable. What's more, it has the typical shonen tropes: the enemies grow in scale, with a normal enemy in volume 15 (for example) being much more powerful than its analogue in the first volumes. There are, however, a number of things that I'm sure inspired Attack on Titan: the story has a lot of similarities, except that Attack on Titan does them well. The similarities are much more evident in the middle volumes and fade as the story progresses. Another problem is the plot armour of some characters, which is all too evident in the final volumes. The ending is predictable but quite well made.
Art - 7.5/10
The artwork is superb and the action scenes are some of the best I've seen in manga. The scenery is detailed and carries with it an atmosphere befitting the manga. Why 7.5? Character design has a lot of problems, to the point where characters are only recognisable by their hair and, in one case, their arm (no joke).
Characters - 7/10
As I wrote in the previous section, most of the characters are not memorable and are almost impossible to identify in the manga. However, because of their importance in the narrative and their personalities, there are a number of characters that are memorable - such as Clare, Miria or Teresa. This is remarkable, as they are living proof that they have their own personalities to be individualised. From a technical point of view, it also helps that they often repeat the characters' names, which makes it easier when the art doesn't aid.
Enjoyment - 7/10
Claymore is an enjoyable reading experience. The overwhelming majority of the panels are combat panels, so it reads very quickly, allowing you to “switch off your brain”. The story is very easy to follow and is constructed so that your attention doesn't wander. If you're looking for a manga that allows you to unwind and relax, Claymore fulfils that function, but if you're looking for epic stories like Fullmetal Alchemist, Berserk or Attack on Titan, I wouldn't recommend it. Overall, though, it's a well-done manga that deserves a recommendation.
