Watchful eyes on YouTube caught an early glimpse of the collaboration between Valve and Team Overkill. Guess what? It turned out to be a Left 4 Dead prequel the same way that Prometheus is one for Alien/Aliens.
Uploaded onto the Overkill YouTube channel and then quickly removed, the DLC mission "No Mercy" is purely inside Payday: The Heist's world. Based on what's overheard in the gameplay trailer, you and three other cons enter a familiar building for the Left 4 Dead crowd: Mercy Hospital. The video was pulled and later Kotaku received the following statement from Valve:
""This is a 100% Overkill made mission for Payday: Heist simply set in no mercy hospital from the Left 4 Dead series. It is not telling the origins of the Infection and is not canon. There is a little cameo from one of the L4D characters (the comic should give you a hint) and a fun little easter egg with a payoff later in Left 4 Dead. Just us having some fun with a studio we are friends with and who have also made a great co-op game."
The goal of the level? Secure blood from an "infected" person in quarentine. And then survive the hallway shootouts with SWAT and other police officers.
There's no other info about "No Mercy," but it's a fun way to bring these two co-op universes together.
