There are two different endings in Darksiders 3. You will receive the first after the usual completion of the game. You need kill of all the Seven Mortal Sins and the traitor. If you want to get alternative ending, go on the Scar location. Go back before you jump over to the wasteland with a hurricane. There is an air flow on the right ledge, where a huge monster is. Use a flow and Storm Hollow to go up and enter the elevator to find yourself in the lair of Abraxas.
You have to kill Abraxas to get his soul. After that, with the help of any portal, return to the rooms of the Lord of the Void and talk to him. Be sure to spare him. He will leave a mysterious stone amulet. The Rage will pick it up automatically, and the amulet will be placed in an empty inventory slot. Throughout the game, the amulet does not bring any benefit, but in the end you will see a completely different cut-scene with small additions.
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