Amphiaraus was one of the seven kings against Thebes. Foreseeing his own fate, he concealed himself, to avoid going to the war; but his wife Eriphyle, bribed by a diamond necklace (as famous in ancient story as the Cardinal de Rohan’s in modern), revealed his hiding-place, and he went to his doom with the others.

Aeschylus, The Seven Against Thebes :⁠—

“I will tell of the sixth, a man most prudent and in valor the best, the seer, the mighty Amphiaraus.⁠ ⁠… And through his mouth he gives utterance to this speech⁠ ⁠… ‘I, for my part, in very truth shall fatten this soil, seer as I am, buried beneath a hostile earth.’ ”