I cleared the Battlefields first dungeon and all the non dungeon areas all around before I got there to fight DKs. I also had a very big number of portions on me and used a lot the spacebar key. I completed the easy quest with the Doctor in the infirmary to get some more xp and then I went to the first right turn on the drill map. There is a DK there but also there is a room that unlocks the second Battlefield dungeon. I went to clear all the dungeon there. Got some very special weapons for me and my DK. So the Drill area gets more easy to clear up.
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