There are 6 new runes for Warlocks to discover in SoD Phase 3 ... Runes are a powerful new system in WoW Classic: Season of Discovery allowing stronger and more varied playstyles to the game ...

Engrave your chest or robe with the Soul Siphon rune: Increases the amount drained by your Drain Life and Drain Soul spells by an additional 6% for each of your Warlock Shadow effects afflicting ...