Lies of P Fallen Archbishop Andreus boss guide

How do you beat the Lies of P Fallen Archbishop Andreus boss? The twisted Lovecraftian eldritch horror that is Fallen Archbishop Andreus shows up relatively early in this Soulslike, being only the fifth mandatory boss. He's likely the first one you'll struggle with, because he takes it up a level in terms of difficulty compared to the fights you've encountered so far - though King's Flame, Fuoco, was no pushover either.
So if you're wondering how to beat Fallen Archbishop Andreus, we can help. Once you're past him, you'll wonder how you ever struggled when you see how tough some of the later Lies of P bosses are, but he can feel like a brick wall when you first encounter him. With the best Lies of P weapons and the best Lies of P legion arms in hand, here's our guide to beating the Lies of P Fallen Archbishop Andreus boss fight.
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