Elden Ring’s Frenzied Flame ending — in which the player character becomes the Lord of Chaos and burns away all grace — is the most nihilistic optional path in the game. Reaching it requires the Three Fingers encounter: descending to the game’s deepest level, removing all armour, and allowing the Three Fingers to brand the player.
The Three Fingers are not an Outer God in the conventional sense. Their ‘advice’ — burn everything — is presented as the only answer they know to a world corrupted beyond repair. The Frenzied Flame is not malevolence; it is the conclusion of something that has watched too long and stopped believing in selective solutions.
What distinguishes this ending from others: it is the only ending that cannot be planned for without commitment. The Three Fingers branding changes the player’s ending lock unless a specific NPC questline provides a reversal — and that questline requires having been told about the reversal before the branding occurs.
FromSoftware built their darkest ending to require the player to make an uninformed commitment — to agree to something they don’t fully understand before they learn whether they can change their mind.

Detail work in areas most players never visit separates great games from good ones.
200 hours in and I never caught this. The developers really reward obsessive players.