This Achievement can be obtained on the Fourth level of the game "
Mount Tsuru".
Using
Mugen find one of the multiple rocks that can be picked up on the level. Once you have one find a one of the many guards and use the "
throw" technique from your skill bar and aim it towards the guard this will kill them instantly and the achievement will pop. (Use Aiko's distraction to cause a guard to face away and be stationary)
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