Karmanal of Zert
Indestructible, soulless monsters that appear briefly in the 1971 fantasy novel The Queen of Swords by Michael Moorcock. The sing before feasting.
Over the valley now came hopping things. They hopped on several legs and from their bodies sprouted a dozen or more tentacles. Their huge eyes rolled, their massive fangs clashed.
“The Karmanal of Zert,” Jhary said in mild surprise as he dropped the reins and armed himself with sword and poinard. “I have encountered these before.”
“How did you escape them?” Rhalina asked.
“I was at that time companion to a champion who had the power to destroy them."
“I, too, have a power,” Corum said grimly, raising his hand to his eye. But Jhary shook his head and grimaced.
"I fear not. The Karmanal of Zert are indestructible. Both Law and Chaos have, in their time, taken steps to do away with them—they are fickle creatures who fight for one side or another without apparent reason. They have no souls, no true existence."
"Therefore they should not be able to harm us!"
The laughter ran on.
"I agree that, logically, they should not be able to harm us," Jhary answered equably. “But I am afraid that they can.”
About ten of the hopping creatures were nearing their chariot, weaving between the statuelike warriors. And they were singing.
“The Karmanal of Zert always sing before they feast,” Jhary told them.