It becomes obvious that Nathan Hale is just bits away from becoming a complete chimera, but he fights on to stop Daedalus. After fighting through hell and killing the big bad, he is on his way out of the facility with some new powers he obtained highlander style from Daedalus. While trying to escape the facility that is crumbling around him he meets up with his squad mate, Capelli. Nathan doesn't seem to care though. He looks off into the distance at a giant chimera ship and says,
"Can you hear them? They are calling to us. It's beautiful."
As Nathan approaches Capelli, Capelli pulls out his pistol and reluctantly pulls the trigger as Nathan says with an inhuman radiance,
"This is just the beginning."
They kill the only character you even give a crap about, you're character. On top of that, even though you killed Daedalus, it looks like the Chimera aren't stopping the fight. Sad day.