When this Adventures in the Magic Kingdom Nintendo Entertainment System prototype appeared on eBay in May 2011 from a seller named Annick Wolkan, I had an inclination that it could be special based on the fact that a DuckTales pre-release cartridge with a similar label contained many interesting differences. Turns out, I was right for a change.

The EPROM chips on the official Nintendo NES-SKWEPROM-01 development board inside are devoid of any Capcom company stickers.

There is a white soldering wire on the back of the circuit board.

(Image source: Google Earth)

This prototype came all the way from Hollywood, California, about 300 miles north of Capcom's former Santa Clara headquarters.


Continue Option
In the retail version, the Continue option only appears after losing all of your lives. In this prototype, however, the option appears before even starting a new game.


Requires Flash10

Unreleased Yoko Shimomura Music Track (Download Full .NSF File [ripped by Chris Covell] & .MP3 Sample)
The retail game plays the Mickey Mouse Club theme song during the opening cutscene. This prototype uses a different song that is not heard anywhere in the retail game.


Text Sound Effects (Download .MP3 Sample)
The prototype uses a loud, rather annoying typewriting sound effect for whenever text appears. No such sound effect exists in the retail game.


It's Not Polite To Point
The flashing, downward-pointing arrow is missing at the end of the prototype's cutscenes.


Select Screen Changes
Pressing Select pulls up a menu where you can use the stars that you've collected to replenish health, briefly become invincible, freeze enemies, or gain an extra life. The prototype requires fewer stars to purchase these items.


Missing Main Street, U.S.A. Store Rooftop Sprites
The sprites on the rooftops of the Main Street, U.S.A. stores are not yet implemented in the prototype. (Now where am I going to find the souvenir top hats?)


L-A-Z-Y. E-Y-E. Why?
Mickey Mouse seems distracted in the prototype version, as his eyes stare away from you during several cutscenes and on the Select menu. Or maybe Mickey just has a terrible case of lazy eye?


Space Mountain Lettered Stars Not Displayed
Mickey instructs you to find the silver key on Star "F," but the prototype does not display any letters on the HUD. "F" the alphabet!


Projectile Dysfunction
In the prototype, blue-colored lasers, not missiles, are fired at asteroids. In the retail, the laser sprites are used only when blasting incoming enemy spaceships/Star Destroyer rip-offs.


No Congratulations Music
Music does not play after you beat an attraction, only the aforementioned irritating text sound effect.


No Game Over Music
In addition to that, the game does not play any music when you lose.


Map Music Plays Before Attraction Begins
At the start of an attraction, when Mickey is briefing you, the map background music continues to play.


New Autopia Drawbridge Sprites
The Autopia drawbridge in the prototype version uses more realistic-looking sprites than the "extending bridge" graphics in the retail version.

Failing to wait until the drawbridge comes down runs you the risk of driving right into the water. I suppose that these sprites might have confused some players into thinking that they could use the drawbridge as a ramp.


Look at Me When I'm Talking to You!
If you approach one of the kids from the side or from behind to trigger the trivia game, your character will be turned to look directly forward. In the prototype, your cowboy has poor social skills and shows no such politeness.


Dog-Loving Girl Repositioned
During the trivia game, the girl with the dog is placed a little higher up on the map in the prototype, so much so that her bouffant gets in the way of the white text box.


Dog-Loving Guy Repositioned
Also during the trivia game, the boy with the dog is placed a little higher up on the map in the prototype version.


Pirate-Tosser Cannonball Color
The prototype cannonballs that the bearded pirates carry and throw at you in the Pirates of the Caribbean attraction are painted a different brown. As a result, they blend in with some of the background.


Boat-Bound Cannonball Color
The prototype cannonballs that drop from the sky during the boating portions of Pirates of the Caribbean are painted a deeper blue.


Scorpion Surprise
The prototype adds a scorpion on the platform where the skeleton pirate throws his gold coins, making that section much trickier.


Skeleton Pirate Throws Like a Girl
To make up for the missing scorpion, the skeleton pirate's throwing radius is far greater in the retail game. In the prototype, once you're on the ladder, you're safe.


Candle in the Wind
The prototype candle item in Pirates of the Caribbean hangs to the right of the ladder instead of to the left.


Pirate-Cannon-Firing Cannonball Color
The prototype cannonballs that the seated pirates fire at you are painted red with a teal blue shine. The ones seen in the retail game match the pirates' attire: dark blue with a gray shine.


Some Like It Hot
As our little cowboy makes his voyage out on the final paddle boat in Pirates of the Caribbean, the flames from the kindling rise and fall in the prototype. The prototype's logs are positioned slightly closer to the water, as well.


Zombies Hock Loogies Without Warning
In the retail game, zombies are courteous enough to pause for a good two to three seconds to let you know that they're hocking up a ghostly loogie. Not so in the prototype—these guys keep on walking as they're clearing their throats of evil, never missing a beat.


Flying Ghouls Are Cheap Bastards
The flying ghouls are another reason why The Haunted Mansion stage is much more difficult in the prototype. After getting through the library in the mansion, you have to do some platform jumping on chairs that fall once you plant your feet on them. The problem is, when you reach the second chair, a low-flying ghoul always materializes where you have to land, causing you to fall.

To combat this creep, throw a candle while you're on the first chair and just hope that the flame hits its target when the cheap bastard spawns. An even easier technique is, when you reach the first chair, press Select and then use your stars to purchase Freeze to keep the ghoulie at bay, or Invincible to out-ghost his apparition ass.

In the retail game, this flying ghoul comes after you land on the second chair, not while you're making your careful landing.


Y'All Come Back Now, Ya Hear?
Big Thunder Mountain Railroad's opening text in the prototype has Mickey speaking in a more dialectic, Southern drawl. Bless gracious! Dat dar ‘twa’n’ no good, honey.


Time's the Limit
In the prototype, the time limit displays three digits instead of two.


More Rocking, More Rolling
An extra boulder rolls across the track in the prototype at the first right turn.


Dead-End Track #1
There's a dead-end track at the first left turn that does not appear in the retail version.


Dead-End Track #2
If you continue down the first right turn, you'll wind up going into a dead-end track in the prototype.


Borderless Stars
The star icons scattered around Big Thunder Mountain Railroad do not have white borders. Counting as five points each, they were meant to stand out from regular stars.


Dead-End Track #3
If you keep riding the right side past the first star, you'll see another dead-end track that does not appear in the retail game.


Dead-End Track #4
Are you seeing a pattern here? Past the bridge, and on the far right, you'll come across another dead-end.


Dead-End Track #5
Keep going through the dig site on the right-hand side, and this dead-end threatens to end your train ride.


Wide Gap
Near the end of the level, on the far right around the patches of cacti, the gap between the right and left tracks has narrowed.


In the retail game, the stations at the end are marked by numbers, and your train has to arrive at the one where Mickey tells you to go. The stations have not yet been assigned their numbers in the prototype version, but the GOAL sprite is marked to let you know which one to choose.


In the prototype, if you ride the left-hand track past the bridge, you can derail your train but still continue downward after you're no longer on the track. The barrier in the retail version prevents this from happening.

You can also derail at other parts of the ride, like at dead-ends, by slowing down while making a turn. The key is to make the turn at the precise moment so that the train moves over the top of the barrier, and then immediately slow up.

Using this method at the fossil dig site area, you can derail from the left track and then keep going left until the train goes off screen. The train will soon reappear on the opposite side of the screen, on the far right track. Things do not go back to normal, however, as the game still thinks that you're on the left track. So when the right track starts to curve right, the train goes off screen again and you wind up back on the left side. That is, unless you slow your speed and press down on the Control Pad; then you head straight through the terrain.


Rocky Roadblock
A boulder blocks the track on the far left in the mine car graveyard.


Track Detour #1
After the mine cars, the far left track turns into two straightaway tracks in the prototype.


Track Detour #2
Also after the mine cars, there is an extra straightaway in the prototype.


Track Detour #3
Yet another track in the prototype, this time near the final stretch of Big Thunder Mountain Railroad.


Game Over, Man
When you lose all of your lives in the retail version, you're taken to the Game Over screen and then automatically back to the title screen where the Continue option will be highlighted. In the prototype, though, the Game Over screen remains until you press Start, at which point the Start option will be highlighted instead.