It has been confirmed that there will be a character death in season 2. Also, in the end page code of Weirdmagddon Part 1, it says:
GAME IS OVER, AND I WON. NOW IT'S TIME TO START THE FUN. I ALWAYS LOVE CORRUPTING LIVES. NOW LET'S SEE WHICH PINES SURVIVES.
So one of the Pines will die.
I think it might be Stan who dies. If he dies though, I am gonna cry forever. ,._.,