Earth is no longer just a battlefield.

It has become a signal to the stars.

As hybrid mutations spread and civilizations collapse, the mysterious alien artifact known as The Catalyst activates—triggering a transformation that threatens both humans and kangaroos alike.

While chaos spreads across the planet, Sarah and Ryl uncover the terrifying truth behind the Catalyst: it was designed to summon an ancient extraterrestrial species known only as The Architects.

With time running out, Koa leads a dangerous mission into the Broker’s fortress to destroy the signal before the alien arrival begins.

But when the sky begins to change and massive structures appear above Earth, one thing becomes clear:

The rebellion was never the real war.

It was only the preparation.

And the Architects are coming.