Master Demon-Slaying Rune is a Rune in Dragon Age: Inquisition (DAI). Runes are special upgrades applicable to special slots in Weapons. All runes raise the basic attack power of a weapon for a specific amount, depending on if it is an elemental or "slaying" rune and the rune's tier; elemental runes do not raise the attack power of a weapon as much as slayer runes, but allow preying on elemental weaknesses, and superb runes naturally have more power than lower tiers.
Master Demon-Slaying Rune Effect
Master Demon-Slaying Rune Materials