Death Stranding: 21 WTF Moments You Need To See To Believe
4. Twist! Amelie Is The REAL Villain (Kinda)
Though it wasn't hugely surprising given that the game flat-out refers to her as an Extinction Entity long before the ending, Amelie is ultimately revealed to be Death Stranding's kinda-sorta ultimate antagonist.
It turns out that Higgs was being used as a pawn by her to hasten the onset of a sixth Death Stranding which would annihilate the United States, even if she eventually grew to second-guess her decision.
As such, she gives Sam a choice at the end of the game, to either end the world quickly with the Final Stranding or postpone it and allow humanity a chance to endure (despite Amelie claiming the Stranding is inevitable).
Sam opts for the latter, ending the game on a relatively hopeful note for humanity's future, even while Amelie, for her sins, is left stranded alone on her own Beach.