Flintlock: The Siege of Dawn

For the blunt melee weapon, I decided to upgrade the sunderer's hammer. It doesn't need Iron or sulfur to upgrade, however, it does require cursed stones. The first stone {raw cursed jade} is found in the City of Rit. It's on the western side in an ally. Nor/ Enki will make a comment about these boxes were moved. Jump up the boxes and you'll see a chest, along with a horde of dead. Clear the dead and you'll be able to grab this chest. I forgot how much reputation is needed for the upgrade, but I believe it was 6,000.

The second stone can be found in the three peaks area around the "F" in Flooded Pit. This path is part of the main story line. The chest with the stone is somewhat hidden. At one point in this path, you'll have to climb a ladder. Once at the top turn around, you'll see a ledge on the right side with a skeleton corpse. Follow this small cave to the end for the chest containing the stone. This stone is used to upgrade Sunder's Hammer from level 4 to 5 with a cost of 12,000 reputation.

The third stone, raw cursed ruby, is located in three peaks as well in the Black Powder Factory. You'll need to find a breaching barrel to blow up a wall to reveal the hidden chest. Its towards the end of the factory, the map will make it seem like you're in Needing Keep. A breaching barrel will be on the map as well and this is where the chest is located. Now with 27,000 Rep the achievement will be yours!