A Halem'nite priest who presides over the Journey of the Mother Compeer in 3191, believing that its winners must give their lives so that the gods will send rain.
Ohvahz appears in Whistlespeak. His people survive in the one green region of a dust-choked world, sheltered by a mountain they hold sacred. It is in fact an ageing Denobulan weather tower.
He welcomes the disguised Burnham and Tilly and lets Tilly run the ritual race, which she completes alongside his child Ravah. Only then do the visitors learn that the winners are sealed in the temple chamber to die. Ohvahz grieves for Ravah but will not defy what he believes the gods require.
With the two trapped and suffocating, Burnham beams in and tells him the truth about the tower. He opens the chamber. Afterwards she shows him how to maintain the machinery so that no further sacrifice is needed.