• Unlimited Weapons/Energy/Shields : D+3+4+6+7 (tone confirms)
• Extra Lives (limit = 9) : 3+6+9+# " " * Level Skip : 2+4+6+7+8+9 " "
• Toggle Day/Night (during gameplay): U+A+B+C+7

Easter Eggs (at Mission Select Screen, unless otherwise noted):

• Change Globe Speed/Direction : 4+6
• Change Globe Size (CD only) : U/D
• Alternate External Monitor Frame : R+C+1+4+5
• Alternate Ground Texture (during gameplay) : U+A+B+C+3
• Debug Mode (during gameplay) : U+A+B+C+6
• Change Music Tracks (during gameplay) : U+A+B+C+0 (Cart.only)
• Enable Secret Bonus Missions (at Mission Select Screen):
• Level 1 = U+2+3+6
• Level 2 = D+2+6+7+8
• Level 3 = R+3+5+6
• Level 4 = U+2+5+8
• Level 5 = R+2+4+5+6