Baldur's Gate 3 endings explained

How does Baldur's Gate 3 end? If you want to know what to expect or perhaps fancy planning out the best possible ending for your playthrough, you'll be glad to know that there are many, many endings in this gargantuan RPG.
We already know that Larian's latest is a long game and there are tons of possibilities and outcomes for every roll of the dice, along with an impressive roster of Baldur's Gate 3 classes and BG3 races you can choose when the Baldur's Gate 3 release date arrives. So, just how many endings are there in Baldur's Gate 3, and how do they differ from each other?
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