Play the first level there is two battles in which you will have to fight. When fighting these battles avoid doing the jump attacks as you are likely to get hit on the way down. Instead just continuously hit the "x" button if they are about to raise there weapons do a quick "y" which will kick them away. In the second battle there will be alot more guys just do the above strategy but jump back when you kill the lot and more come down the stairs. Falling off the ledge causing a instant death will not matter towards this achievement. If you happen to fall off a small ledge tho and inflict any type of damage to your self just restart the level.
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