PlayStation Now allows players to stream classic PlayStation titles on the PlayStation 4 or PC. Red Dead Redemption is an open world western action-adventure video game that made its debut in 2010, while Undead Nightmare is a standalone DLC expansion that added a zombie horror-themed single-player campaign. The sequel, Red Dead Redemption 2, will come out in 2017.
Rockstar Games has announced that the PlayStation 3 versions of Red Dead Redemption and Undead Nightmare are both coming to the PlayStation Now service on December 6.
Source: Press Release