Hey, guys. From this official Facebook page on the 123 Slaughter Me Street series, along with confirming the second game's upcoming update, the latest post reveals the image of pixelated-version of the trio from the second game, possibly hinting another Retro game. I'm not sure if this is officially real or just a fan-art.
Let's hope if this is actually real. If that's the case, then I'm hyped as well!
EDIT: The image actually turns out to be fake, but the game is still considered by the developers.