WHAT IS 52ND ENDING THEORY? AS WE LEARN FROM THE TRAILER, THE SIRENS ARE ON, EVEN IF THE TANGOMANGLES DIDN'T ESCAPE. THE CARL RUN TO THE BUNKER, BUT IT EXPLODES. THEN YOU REALISE THAN SOMETHING BAD IS HAPPENING. AFTER THAT NEGATIVE HOUSE EXPLODES AND YOU ENTER DIAMOND HOUSE. MY EXPLANATION OF MY THEORY,IS THAT IT IS THE END OF THE WORLD ENDING.