We all saw Bill die in a fire along with Stanley, but is the triangle guy we all love to hate truly dead and gone? Take a look at this video I found on YouTube:

From the looks of things, we may indeed be meeting Bill again on a sunny day. We may not know when or where, but I personally think we may see Bill Cipher make his triumphant return. What say you guys?

He will probably return in some sort of GF comic series.