>Shadow Force hits a target even if it has used Spiky Shield, King's Shield, or Mat Block, removes that protection for the rest of the turn, and the user of Shadow Force does not suffer the negative effect of that protection move (if any).
So Shadow Force will be able to attack Aegislash when using King's Shield, and Shadow Force can also hit any other protecting move like Protect and Detect, etc.
Hope I helped. :)
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