When it comes to bands operating in the Viking/pagan/folk-metal field, the line between glorious victory and shameful defeat, rousing anthems and laughable jigs, can be a fine one indeed; yet Finland's Ensiferum have landed on the positive side of that line more often than most of their peers over the years.

In part, this success can probably be attributed to the band's particular spin on the style, which features a balanced display of melodic accessibility (derived from power metal, primarily) and unmitigated metallic violence (this from death and black metal), and is therefore likable to greater numbers of noncommittal metal fans than bands working exclusively in either extreme.

But one also cannot overlook Ensiferum's simply engaging songs and cautious sonic tinkering from album to album -- both of which remain very much in evidence on the group's long-brewing fifth studio long-player, 2012's Unsung Heroes.

On this occasion, it's the Iron Maiden-created, speed-metal-enhanced power gallop -- a key component on most Ensiferum albums past -- that's conspicuously demoted to a lesser role, and while it eventually resurfaces with a vengeance on the blistering "Retribution Shall Be Mine," its absence on mid-paced paeans to ancient splendor such as "In My Sword I Trust" and "Burning Leaves" arguably lends them even greater gravitas and majesty.

Further departures from safe ground include, on the upside, the title track's quiet, flute-led mid-section, and the folk fairy vocals of "Celestial Bond"; on the downside, actor Vesa-Matti Loiri's overly dramatic narrations on "Pohjola" and the sketchy baritone vocals used on "Last Breath" (think Quorthon of Bathory, and not on his better days).

Backing up just a bit, you'd be hard pressed to find a more suitable, stage-setting instrumental introduction than "Symbols," which paints vivid, panoramic images of proud Norse adventurers poised on a cliff's edge, braids flapping in the wind, steely eyes piercing the infinite horizon for a glimpse of Valhalla.

But you may also have a hard time endorsing the album's closing, 17-minute mega-epic "Passion, Proof, Power," which packs the whole kit and caboodle -- opera, prog, pomp, barnyard sound effects (!), you name it -- and many an awkward transition in between them -- often more to its detriment than its credit.

Excepting this last, unusually ill-advised leap of faith, though (and let's not even get into the deluxe CD edition's bonus track: a cover of the Gypsy Kings' "Bamboleo"!), Ensiferum once again escape their Unsung Heroes adventure relatively unscathed and ultimately victorious.