How to farm Diablo 4 Forgotten Souls

How do you farm Forgotten Souls in Diablo 4? Diablo 4 isn't over once you've completed the campaign. There is a whole new world of endgame content to discover, alongside seasonal stories and features, and Helltide events are just one of those post-campaign mechanics. They're also the best way to farm valuable resources including Forgotten Souls.
D4 Forgotten Souls are a D4 salvage item, though the best way to get them in greater quantities is via Helltide events, as you'll need to salvage some pretty valuable gear to even get a chance at seeing a Forgotten Soul. They're used to upgrade Sacred and Ancestral weapons, and you need them in order to perfect your best D4 builds in the RPG game, so here's how to farm Forgotten Souls after Diablo 4 endgame.
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