As long as you have not taken damage in the last 5 seconds you gain a protective shield that absorbs the next 60% of your Life in damage.
"Power begets power. The excess energy from one spell is absorbed by the other, and so the effect is sustained." —Excerpt from Grand Master Clavaught's Lecture on Synergistic Effects in Esoteric Arcane Spheres
Note: Information on this page is based on a level 70 character.