I can confirm that besides the Undead Nightmare Pack, this disc also includes the Liars and Cheats Pack & the Legends and Killers Pack.
However the Liars and Cheats Pack & the Legends and Killers Pack can only be utilized while the Undead Nightmare disc is inserted into your PS3.
Undead nightmare is a great ad-on to red dead redemption. Red dead was a pro game when I got it. This was the second most well played game I have played on the ps3. Then when I stopped playing it for a while. Put it wasnt long until Undead nightmare came out. This is a really good game. The campaign is a decent length. Theres plenty to do. I like goin out and saving people, i like the missions, capturing the horses of the apocalypse, saving towns from the dead and also the online undead overrun. This is a good ad-on, well done Rockstar you made a great job of the GTA IV ad-ons and now you have done a great red dead ad-on. I really would like it if rockstar are to make a red dead redemption 2. L.A. Noire is rockstars next game, if rockstar make good games like red dead and GTA then this new game should be good. Now you survive the undead overrun.