Defection

"Hmm, that makes sense."

William nodded in agreement.

The Ancient Humans in Halo were highly advanced in biotechnology.

In Halo 4, which William had cleared several times, the Librarian had even mentioned this aspect and upgraded Master Chief once.

If "gods" like Hades and Athena were actually descendants of Ancient Humans who had survived the technological regression and the Halo Array's activation, then that would indeed explain all those "abnormal" phenomena.

"That's why I said that any supernatural event labeled an 'abnormal phenomenon' is merely something our current technology and knowledge are completely unable to understand.

"Once our level reaches a certain point, any supernatural event can be explained naturally.

"Just like the Forerunner race...

"I can't speak for the entire universe, but at least as far as the civilizations and life-forms in the Milky Way Galaxy are concerned, they're all extremely childish in the Forerunners' eyes."

Halsey, standing to William's left with her arms folded across her chest, voiced her conjecture.

"Mm." William echoed her, then asked, "So... if the Flood appears, how should we prevent it?"

"Well..." Halsey furrowed her brows and thought for a moment before looking up at William and saying, "Based on your description, the Flood is indeed an extremely difficult species to deal with.

"However, with the current Individual Equipment of the UNSC and our forces, their sealed construction is sufficient to filter out Flood spores, at least reducing the chance of infection during combat.

"Also, the ancient virus released by that Rebel general back then may very well have been related to the Flood.

"It seems we'll need Doctor (049) to come and help us..."

As she spoke, Halsey suggested to William, "William, I believe the xenomorphs can effectively resist the Flood's corrosion, assimilation, and infection.

"After all, xenomorph blood is Corrosive Acid.