With Attack 4 and Enduring 10, a cost of only 4 recruits, and a mechanic to stay on hand, this seems like too much potential damage for a Common. Someone with a mere ten recruits and the standard 3 dungeons could play it seven times in a row for 14 damage each time after the first, all the while accumulating bricks and gems and freely discarding unwanted cards from hand.
I'd suggest either lowering the Enduring value to 2 or adding Production x0 to balance it as a Common. Removing the element to replace another card with Strangling vines would alternately work.