According to a recent post on Reddit, you can get a buggy skin for Rocket League in Dying Light: The Following on Xbox One. The exclusive content allows you to get a Rocket League skin for a buggy to play Rocket League with a friend in Dying Light.
Also announced on Twitter, just go to dockets.dylinglightgame.com and enter code "LIGHTMYROCKET" to redeem. No word yet if we'll see a Dying Light-inspired buggy in Rocket League, but it is highly likely to happen.
Dying Light vs Rocket League
Redeem this code. Get a new buggy skin.
DL-inspired stuff coming to Rocket League too. pic.twitter.com/ZXX0BL2aPs
— Dying Light (@DyingLightGame) March 11, 2016
Dying Light: The Following is new standalone DLC for Dying Light on Xbox One featuring a map that dwarfs the size of the original Dying Light map, and features more gameplay enhancements that improves upon the original Dying Light game. Dying Light: The Following Enhanced Edition includes all of the content of the original plus some new exclusive features.