Crystal Darts can be used to cause Golem Smiths to aggro any nearby target, including other enemies. Hitting them with 4 darts causes this to proc, and any more once in the state will reset the condition. Golem's weakness is the back. Hitting the back will deal significantly more damage. They're most vulnerable immediately after attacking. Ambush Shard will almost always hit the stone golem in it's weak spot.