Author : For those who don't get what Amity did since she has no guarantee that Hunter will let her & King go after she give him the key, she throws it at the opposite direction to distract him and hit him with her abomination fist so that she & King will have enough time to escape and make sure he won't follow them.
And because Hunter only go to the mission is to make sure Kikimora didn't fail it he decided to give the key to Kikimora so she would give it to Belos.
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