Boon of Abyss Mastery (5e Epic Boon)
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Boon of Abyss Mastery
If a character reaches the bottom Gate of the Abyss of Starfall, found at The Neo Greater Material Plane (5e Environment), the DM can grant this boon. If not using this homebrew plane, a similar appropriate achievement can be decided upon by the DM.
You become immune to the Dark Oppression effects of Starfall's caves, and become immune to the effects of the Abyssal Corruption optional rule, if that rule is being used within the campaign.
Additionally, fiends from the Abyss will be more reluctant to confront, fight, or anger the character that has this Boon, along with any they know are allied with the character. The extent of this is up to the DM's discretion, but at the very least, if the character doesn't cause trouble in the Abyss, no normal fiend (With a CR or level less than or equal to the player's level) should turn to them to steal a soul.