This is not a direct "resource" for Overwatch. The people in this video will not give you any tips and tricks, nor will they guide you through any maps. Instead, this video explores the way sound is used as a whole in Overwatch. Again, while not an actual guide or resource -- this video is invaluable for understanding the sound design and techniques used in Overwatch.
Although it is not generally suggested you should exactly mirror any professional player's settings... looking at what is typically used might help you when checking out new hardware, or trying to adjust your settings.
A detailed guide on the very specific subject of crosshair customization. This guide provides a helpful image album showing different crosshairs and their settings, as well as detailed written information on choosing the crosshair that will work best for you.
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