I can honestly state that I didn't expect εpsilon to turn out as good as it did. The exact reason I initially dismissed this album (the inclusion of a full-time female vocalist) turns out to be one of its greater strengths. I prefer to separate Blood Stain Child's career into two polarizing camps. I consider Mystic Your Heart the culmination of their melodic death appeal, and now εpsilon appears to embody the best of what the band has had to offer since they started flirting with the whole "trance metal" concept.
I really can't even appraise this as a proper metal album, because the heavier end of the spectrum makes such fleeting appearances. The first track "Sirius IV" features a lot of stop-start riffing syncopated with the drums akin to All That Remains that coexists marginally well with the female vocals. This style persists, teasing with bouts of heavier riffing, until "Stargazer". This is one of the least metal songs on here but also the best, the keyboards evoke great atmosphere and the chorus is infectious. Sophia's vocals, while perhaps not technically mind blowing, fit quite well within the confines of the music. For a female vocalist, her inflection is deeper than most, and she handles the lion's share of εpsilon quite well. I'm not even kidding, there are more female vocals than Ryo's parched scream here. "Merry-Go-Round" even features some near-acapella moments which probably feature the female vocals at their most impressive in isolated environs. The infamous Engrish lyrics also seem to be rectified for the most part here, which is a relief with the clearer vocal delivery.
The keyboards deliver a performance that runs parallel to Mozaíq in most respects, if not even more brazen. There are no keyboard solos, or really any leads of any kind. The keyboards are all programmed, sequenced, throbbing trance backings that help lay the groundwork for most of the melodies. The new drummer, Gami, fills the void left from Violator's departure, but doesn't do a whole lot to separate himself from Blood Stain Child's earlier material. There are some near-blistering double bass passages and blasting but again, this only surfaces in sporadic bursts depending on what track the listener is on. The guitars sound better than ever sonically, but tend to devolve into the aforementioned stop-start riffing pattern which can grow stale on it's own. In fact, there is only one full, proper metal track: "La+"; featuring more of the riffing style that hearkens back to the group's earlier material. It isn't nearly as big of a hurdle as one would imagine, however, as the vocals and keyboards dominate the bulk of εpsilon, making the guitars actually something of an afterthought.
The album features one amazing highpoint and a handful of really good tracks, with only "Unlimited Alchemist" and "Electricity" failing to make a strong case for their existence. It remains something of a shame that the band parted ways with Sophia shortly after εpsilon's release, as she really added a great counterpoint to Blood Stain Child's present sound. I am not embarrassed to admit that I really enjoy this album, it is easily their best since Mystic Your Heart.