Developers Baldur’s Gate 3 claimed that the players are waiting for about 17,000 different endings. The whole team went through this game as diversely as possible to tell you how to get all the good and bad endings, as well as the secret scenario where Gale comes to the rescue of the main character.
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How many endings are there in Baldur’s Gate 3
In the final choice, join the illithids and help them take over the world, or destroy them, freeing the universe from tyranny and slavery. That’s why there are only two headboards: Good And bad. They, in turn, can be divided into twelve. The rest of the 16,988 endings are various relationships with factions, quest characters, and allies.
How to get all the good endings
To successfully complete the game, you must destroy the Netherian Brain, as well as all the illithids and their larvae. This way you stop the invaders and get different unique character development scenes depending on the method.
How to get a good ‘Big Hero’ ending

Once you reach the Netherian Brain, use your mind to command it to self-destruct. This will cause a chain reaction, resulting in the death of all illithid larvae. To get this ending, take neutral or friendly solutions, climb as high as possible to the Netherian Brain and kill all the enemies living in the tower.
How to get a good ending “Emperor Liberator”

If you do not want to make fateful decisions, you can give this burden to the emperor if you take him to the squad for the final battle. You also need to reach the Dutch brain, but the allied illithids will bring about self-destruction. After that, the emperor will receive a new title: “Liberator of the peoples enslaved by the Mind Flayer.”
How to Get the Good Ending “The Emperor and the Hero’s Sacrifice”

Before the final battle, take the emperor to the team, with whom you should have a good relationship. Next, before meeting the Netherian Brain, the allied illithid will tell you a story about a larva he kept for a special occasion. Accept it to transform into an illithid, but keep your consciousness. This will make it easier for you to get into the Netherian brain and take control of it. Seize power with the emperor and destroy the illithid empire. You will win and free the world from the invaders, but you will forever remain in the body of an illithid. After the victory, another scene follows in which Laezel refuses to be your comrade in arms and leaves the squad.
How to Get a Good Ending “Orpheus and the Hero’s Sacrifice”

The next ending is connected to the character Orpheus, who is imprisoned in the Netherian brain. After taking the Emperor’s team, refuse to take a special larva and then free Orpheus. The allied illithids won’t like this, but it won’t cause much trouble. At the final choice at the Netherian Brain, Orpheus will offer himself as a victim. In a new dialogue, offer your help and leave Orpheus as the ruler of your people. Well, after the victory, order a new comrade to kill you. Then you will become a real hero, and even Laezel will mark your sacrifice.
How to Get a Good Ending “Sacrifice of Orpheus”

After saving Orpheus, don’t stop him from becoming a hero. He turns into an illithid and will stop the invasion, but later ask to end his life. This way you save the world, but go into the background and leave no mark on the history of Baldur’s Gate.
How to get all the bad endings
To unlock the evil endings, the player must betray his allies and submit to the will of the Netherian Brain. Depending on the situation, the main character can keep his appearance or become an illithid.
How to get the bad ending “Becoming an Absolute”.

Playing an evil character allows you to follow the path of the Absolute. At the final choice, accept the Netherian Brain’s offer, betray your team and lead the illithid invasion. The enslaved peoples will not thank you, but who are they to condemn your imperial plans?
How to get the evil ending “Emperor Absolute”.

Take the emperor to the detachment, but it no longer matters what kind of relationship is between you. In the final choice, you agree to the terms of the Netherian Brain, but hand over the new responsibilities to your companion. So you keep your appearance, but still enslave the remaining population.
How to get the “Absolutely Single” bad ending

You will again need the emperor in the detachment, and you will also have to accept the conditions of the Dutch brain. This ending differs in that after the dialogue you kill your friend illithid and deal with the remaining allies as well. As a result, you alone will determine the fate of the remaining worlds.
How to get the bad ending “Oath of Bhaal”.

As you progress through the story missions, you will encounter the god Baal. For another bad ending, you must become a follower and take his teachings to the world. Alternatively, when starting a new game, you can choose a ready-made character Dark temptation, who was originally associated with this ancient deity. Thus, the story will turn out to be a complete story, and in the end, having betrayed everyone, you will conquer the worlds in the name of the god Baal. For the final battle, take the Emperor’s team and accept the conditions of the Netherian brain. Then slay the allied illithide for the glory of Baal to become the Absolute, but under the auspices of the ancient deity.
How To Get The Bad Ending “Good In The Name Of Bhaal”

If you become a follower of the old god, you don’t have to follow the teachings of Baal and conquer the worlds. For the final battle, take the emperor to the team and reject the Netherian brain. An allied illithid will help free the humans enslaved by the Mind Flayer, but everything comes at a price. All worlds and creatures are saved except your character. Before breaking the oath, Baal will take control of the hero’s body forever and will personally look for new bloody gifts for himself.
How to get the bad ending “Adoption of the illithide”

If you decide to venture off the beaten track, an unusual ending awaits you. Save Orpheus and turn him into an illithid, then attack him with the whole team. In this case, you fulfill the will of the Dutch brain and you can come and bow to him. You are accepted and turned into an illithide, making the main character part of the plan to conquer the worlds.
How to get the secret ending of the Gale and the bomb

If you have a good relationship with Gale, completed his questline and took him on the final journey, then a different ending awaits you. Once you get to the base of the brain, Gale will tell you that he can self-destruct the Netherian Brain using the orb in his chest. Accept his offer and just watch what happens from the harbor.
If you’ve completed the “Wizard of Waterdeep” quest before Act 2, you can blow yourself up with Gale the first time you encounter the Netherian Brain. The game will end, and the narrator will hint that this was not the end he expected from you, but this will help save Baldur’s Gate, although others will have to fight all the adult larvae.
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Source: VG Times