Consume Essence

During Obi-Wan Kenobi's duel with Darth Maul on Naboo, the former described Maul to have fed on his anger and strength after the mortal wounding of Qui-Gonn Jinn, Maul was gaining strength while he lost his after entering a rage.

More than a hundred years later on Mon Cala, the Emperor Krayt would use this power to preserve his body against the Vong implants that weakened him. So great was the strength he drew from the slaughter around him that he briefly regained his good cheer and boasted that he would not die of the parasites.