说苑/秦楚轂兵，秦王使人使楚，楚王使人戲之曰：「子來亦卜之乎？

The king of Chu had one of his officers speak to him in jest, saying, “Did you make a prognostication before you came here?” “Yes,” said the emissary.

“What was the result?” the officer asked.

“It was auspicious,” said the emissary.

“Oh, but that’s preposterous,” said the officer.

“Your state must lack good turtle plastrons!

The king is going to kill you so that your blood can be smeared on our bells [used in directing troops].