Eb'ben read the translation out loud as you fend off anything coming near him.The crypt wall describes his quest to seek knowledge of the Crystal on Actzen but failed due to his inability to decipher the language. Thus, he wrote what he knew on the walls of his own crypt in his final days.
The Nazru realized that the raw power in the Crystal must have corrupted both him and the dark one. They became so obsessed with power that it drove him to join the dark one, secretly hoping that he could wrestle the power from the dark one someday. While, it drove the dark one to raise an army to wage war on the Nazru population.