While inside the Maw or Torghast, your spells and abilities have a chance to drain a Soul Fragment from your target, granting you 0.3158 × SP Primary stat for 30 sec and stacking up to the maximum stack count times.
When you reach the maximum stack count stacks, unleash Chaos Bane, dealing 47.3684 × SP Shadow damage split between nearby enemies and granting you 9.4737 × SP Primary stat for 15 sec.