Location: Frostspire Mountain
Client: Royalist Sapper
Steps:
You’ll obtain this quest automatically when doing “The Tumbledown Court”. Backtrack to the old tower you just passed on your way to Royalist Sapper. Go inside and you’ll obtain cannon gunpowder. Backtrack to the cannon near the save point, and check it to use the cannon. Go inside the gate that you just destroyed and kill all enemies inside. You just finished the quest; take all treasures inside as a reward for finishing the quest.
Location: Frostspire Mountain
Client: Ibsen
Steps:
WARNING: What I mean by “Ibsen Cave” is the cave where you met Ibsen. Don’t mix it up with another Ibsen cave on the next quest.
You will gain this side quest automatically (when you first meet and talk to Ibsen). You can find the “lost men” at the area between 2nd and 3rd conduit. Defeat the monsters at that place and then talk to the men. Bring them back to Ibsen. Ibsen will give you reward and you can open the treasure chest at this cave.
Location: Frostspire Mountain
Client: Ibsen
Steps:

The cave is located down(south) of 1st conduit stone. Save your game and walk into the cave. Kill Prince Enjekki and other monsters that inhabit this cave. Take the treasure chest and then go back to Ibsen to obtain your reward.