(Polygonal 3D space figurines included and already assembled. May pose choking hazard.)
The "X" forming into position and title attraction sequence were supposed to play sounds, however it is likely they were disabled because the music volume was set way too loud, making the sounds barely audible. Game Genie code F53-50A-081 will enable the unused sounds, while Game Genie code 292-01F-E6E will play the sounds without music.
This game contains the first instance of composer Kazumi Totaka's infamous musical signature. To find it, play Mission 4 and rescue a fake scientist, bringing up an image of a funny face. Wait around 45 seconds on this screen and Totaka's Song will play.
There is a lot of unused text, possibly leftovers from the US prototype known as Lunar Chase.
Document unused text formerly discussed here.