Shadowheart will disapprove if you get the brand. Your interactions here could update the journals for Ask the Goblin Priestess for Help. When first approached True Soul Gut notices you have something special about you and demands to mark your flesh with the sign of The Absolute. Bosses in BG3 are powerful enemies that have increased health and pose a bigger challenge for players.
True Soul Gut is an old goblin woman and the high priestess of The Absolute. True Soul Gut can be found at Shattered Sanctum. True Soul Gut is an NPC and potential Boss in Baldur's Gate 3.