There are many types of illusions that Bayek will encounter while exploring the desert, to receive this trophy you'll need to activate the raining bugs illusion. The best area to trigger the illusions is at the 'Great Sand Sea' during mid-day (simply use the 'Dawn & Dusk' ability to fast travel to this time). There are a large variety of illusions that will appear, which it might take some time before you experience the raining bugs illusion. Simply keep running around in the desert until this illusion appears.

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