For a while, Luke only found stray Mud Dolls, and even though his strategy to fry them up by using Spark Ball worked, he didn't obtain much success while using physical attacks, even though he had two swords with fire and ice attributes. While he could slice them up, it takes too much time to do so, like he had to cut one of the monster's limbs and then freeze it with his Frozen Claymore for it to become unable to return to the monster's body. The fire claymore also worked in the same manner… it took too much time, though.
"It is just like the rules of a game… there are some enemies that, no matter what, are stupidly powerful against physical attacks," Luke said.