ὀλεθριώδης
From LSJ
ἀλλ' ἐπὶ καὶ θανάτῳ φάρμακον κάλλιστον ἑᾶς ἀρετᾶς ἅλιξιν εὑρέσθαι σὺν ἄλλοις → even at the price of death, the fairest way to win his own exploits together with his other companions | but even at the risk of death would find the finest elixir of excellence together with his other companions | but to find, together with other young men, the finest remedy — the remedy of one's own valor — even at the risk of death
