Second disc is a CD with the game soundtrack. Content is the same except:

Forgotten Land (24)
Written (composition, lyrics) and performed by Riverside.

This song is a bonus track and it's not listed on the official tracklist on purpose (hidden track).

Included with the Premium Edition, the Digital Premium Edition, and the Collector's Edition.

Music composed by:
Adam Skorupa & Krzysztof Wierzynkiewicz: 1, 3, 4, 15, 21
Adam Skorupa: 7, 10, 11, 16, 18
Krzysztof Wierzynkiewicz: 2, 5, 6, 8, 9, 12-14, 17, 19, 20, 22, 23

Produced by:
CDPROJEKT RED

Guitars (Tracks: 3,4,13,15,17,23):
Aleksander Grochocki

Vocals (Tracks: 1,2,4,8,19,22):
Iwona Malczewska