It happened, Morty! We got the sauce! That delicious Mulan Szechuan chicken sauce!
You're seeing this right. McDonald's sent Rick and Morty co-creator, Justin Roiland, a half a gallon of their Szechuan sauce. It came in a very hazardous looking container with the label "Dimension C-1998M".
The label on the bottle says:
"For use only in McDonald's restaurants (C-1998M) during limited promotional window, and then maybe again twenty years later. DO NOT SERVE to mad scientists traveling with their teenage grandson; potential non-scientist versions of mad scientists from alternate dimensions; and/or Jerry."
McDonald's also included this letter address to Roiland himself:
Rick & Morty season 3 premieres at 11:30PM ET on July 30th 2017.