Finally deciding less is more, this is the one I went with. My original thought was to have vast numbers of opponents on both sides (at least a dozen) but not only is that hard to show in silhouettes (and I wanted to keep to the same style as the The Forged Prince cover) but, on a cover, it seems like simplicity is more important. More than three elements plus the background is confusing and most often seems jumbled.
A cover should state genre and attract interest, or so I am told. An armored figure with undead should say epic fantasy and the simple Welsh valley backdrop should betray the setting somewhat. As always, the protagonist is accompanied by a black bird, denoting nature, armed combat, and mystery.
In the end I even took away Helgar. The barrow warriors are naked skeletons–although one is wearing a helmet and another is wearing boots (which got cut off)–rather than armored zombies because silhouettes of zombies would have shown little of their supernatural nature.
A lot of books these days just put a sword or medallion or something on the cover and call it good to go. There may be something to that. If I finish the series and sales don’t pick up to where I feel they should be, I might have to give it a try and purchase or commission some.