MArcomage

I like this concept. Why decide to have it cost gems, though?

becasue after many uses of troll or fire elemental you have few recruits.
I'm thinking this card as a support card for recruits based decks.

Also the gems imply magical interference. Echoes of battle could be considered to be dead spirits or the large amount of pain released in the area (not wanting to sound like a psychic medium here :P )

Alright, I'll buy that explanation. =D