Lifting
It is easier to avoid monsters while they are slow and you have both your hands working. Take your time and slowly lift the dumbbells and wait for the monsters to pass by. You will not be able to always lift both dumbbells at the same time. Make sure you always have enough space to avoid the monsters. If the you cannot lift both dumbbells all the way up, he will still lift one to the middle. Because this is unpredictable, alternately lift either side of the weights. If you lose one arm and the monsters are very fast, you should be able to complete a dozen reps before things get out of hand. You have to be very fast and still wait for the monsters to pass.
