Alien: Isolation Achievement

Start up mission 4 and walk around past the reception and continue down the walkway you'll come across an Android with he's back to you slowly walk up to him and use RT twice and then turn and run away back to the start, thus losing him.

Once back at the start start making your way back to him and creep up on him and do the same as before then return back to the start and do this one final time and he will die netting you the achievement.

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