PLEASE NOTE: This trivia may contain spoilers, so completing the game before reading them might be a better option.
The song which Big Al is dancing to early in the game is Robots Must Be Free by Courtney Gears. This may foreshadow Al's eventual transformation into a cyborg, as the song was used as part of Dr. Nefarious' plan in the previous game to promote his idea that organic beings should undergo the transformation into robotic forms.
One of the recently deceased DreadZone competitors is named Agent Zero. Agent Zero was the name of a character from one of Insomniac's earlier games - the second of the Spyro The Dragon PlayStation trilogy.
