Not sure if this counts as a deal, or should be a forum post but for two days only, you can get a Trick or Treat burger from KFC.
The Trick Burger has a zinger fillet, lettuce and spicy korean mayo in a Halloween-inspired bun.
The Treat Burger has a secret recipe fillet, lettuce, chocolate sauce and a cookie in the same Halloween-bun. I dunno how to feel about that. If you try it, please let me know how it is!
Hungryhippo refuse chocolate on a burger