The Simpsons: Bart vs. the Space Mutants (NES)

This page details one or more prototype versions of The Simpsons: Bart vs. the Space Mutants (NES).

Notes

General Differences#

• The score has a simple font with a white color, and it is displayed on the top-right.
  • However, there is some code to handle white-colored numbers. Freezing address $048C to 66 (048C:66) would display numbers 0 to 7. They are always hidden, freezing the address to 81.
• Sound doesn't loop, because the routine to loop the music isn't programmed.
• Outside of the rendition of The Simpsons theme (which is also less refined in this build), the rest of the music was directly ported from one of Imagineering's older titles, Race America.
• Pressing Start makes Bart invincible. This is a debugging effect not present in the final at all.
• Pressing Start + Select skips a level, but you can skip only three levels. Data for a fourth level exists, however skipping the third level instead brings you to a screen of Bart saying "Don't have a cow, man!" (taken from page 42 of the 1990 licensing guide), before sending the player back to the title screen.
• You can't lose, as dying on 1 life does nothing except stop objects.
• The player starts with five lives rather than 3. This is because of the hit counter not being programmed at all.
• The game contains the following items, unused in the final game:

• DOG BONE - Drops bricks by pressing the A button. Stored as RAM address $059D and would've allowed you to place dog bones, rather than bricks.
• MARBLES - Drops marbles by pressing the A button. Stored as RAM address $059F. Functions the same as dog bones.
• SKATEBOARD - Rides you on a skateboard by pressing the A button. Stored as RAM address $05A1.
• BALL - Drops a bouncing ball by pressing the A button. Stored as RAM address $0599. Bounces very high if it hits the ground.
• There are some of the items aren't seen in the final game:
  
• BIRD CALL - This icon would become the Sound Test icon in the final game. Stored as RAM address $059A.
• Some items received changes:
• YOYO - Uses the magnet icon as a placeholder. Stored as RAM address $05A9.
• The level order is different, with Krustyland being level 2 and Springfield Mall being level 4. The Springfield Museum of National History (Level 3) is level 4 in the final version, with Krustyland being level 3 and Springfield Mall being level 2.
• The Springfield Museum is also unbeatable, as after passing through the moon section, is a few screens of empty blackness, where even the HUD disappears. Venturing onward far enough will result in the game crashing.

• The Kwik-E-Mart menu is different. It also shows a pointing hand to indicate what item is selected. The hand is unused in the final, with all of its unique code being deleted.

Proto	Final

• The HUD is different. Lives is spelled "Life", the timer is four digits instead of three, and the level number is shown. In the final version, the level number is removed to make space for the Score. Also, the spray can bar is different.

Title Screen#

Proto	Final

• The window is missing, as is the photo of Grampa.
• The TV design is slightly different, with slightly rougher antennas and lacking the protruding circle part on the back.
• The trademark symbol is was different, bigger with a white coloring instead of black.
• The copyright date is 1990 instead of 1991.

Unused Level#

To do: Find a way to access it properly.

Only three levels are accessible. The fourth level, Springfield Mall, is left unused. To access it, change RAM address $06AD to 04. The level is also under construction, but the character portrait and the name to spell out are implemented.

• For visual clarity, use the following cheat codes: 040D:27 040E:11 040F:20 0410:3F