he joins up with a band of martial arts warriors in order to free the imprisoned Monkey King.
This is not arbitrary. In the early 2010s, CD-Rs (700MB capacity) were still used for archiving. This size fits perfectly on one disc. It also represents the "scene standard" for a 1-hour 45-minute movie (The Forbidden Kingdom runs 104 minutes). A 700MB x264 encode hits roughly 950 kbps video + 128 kbps audio. the forbidden kingdom 2008 bluray 720p 700mb fixed