It should also be mentioned that one's Hollowing level needs to be at least 15 to gain the Luck stat-boosting effect of Hollow-infused weapons. RELATED: Dark Souls 3: Where To Find All Of The Estus Shards More Dark Sigils can be gained from Yoel of Londor (maximum of 5 from this NPC) upon reaching certain thresholds (Hollowing levels 0, 2, 6, 12, and 15). Increasing one's Hollowing level requires the player to both have the Dark Sigil and dying multiple times to further the decomposing process of one's body. The most significant aspect of the gameplay that the Dark Sigils affect is the player's Hollowing level, which determines the outcome of both Yoel of Londor and Yuria of Londor's linked questlines.
The Dark Sigils are not only a sinister mark that can be acquired on the flesh of the Ashen One in Dark Souls 3 but also key items that are crucial to many mechanics that are never really explained thoroughly in-game.