After the 4th heartstone piece, there is a final quest! (northest of the last castle for the alliance, you must kill lord Xin in the empty square southest in the last part of the map!)
No Heartstone Unturned
Dude! You just completed the No Heartstone Unturned achievement in Hands of War and won the No Heartstone Unturned badge and 30 points! Easy!
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