Realistic Onyx stats

"Eventually a compromise was struck. The Builders agreed to construct the Didact's Shields, while simultaneously perfecting their designs for a master weapon called Halo."
(Halo Mythos; Swords and Shields)

"Others had more ambitious solutions. The Didact and the Prometheans faced off against the most extreme faction of Builders, now in complete control of the Council. This faction saw both an opportunity to create ultimate weapons against such a threat, and a way to maximize and make permanent their political power at the same time.

Thus my father and the Master Builder began to design a series of installations, far fewer in number than the proposed Shield Worlds—what would become the Halos.

By radiating a powerful burst of cross-phased supermassive neutrinos, these installations were capable of destroying all life in an entire star system. Properly tuned and powered, they could do more than that—they could kill all neurologically complex life across whole swaths of the galaxy."
(Halo Cryptum; Ch.34)

"My parents were over six thousand years old. My sister and I were barely twelve."
(Halo Cryptum; Ch.27)