Proto:The Bugs Bunny Birthday Blowout
This page details one or more prototype versions of The Bugs Bunny Birthday Blowout.
To do: Compare the unfinished bits of Stage 4 to the final game. |
This prototype of The Bugs Bunny Birthday Blowout is a pretty early build. Layouts for the first four worlds have been worked on, though it isn't possible to complete any of the stages at this point.
The ROM image that had been circulating the internet for many years unfortunately had a number of corrupted bytes, which largely affected tilemaps and level layouts. A clean ROM was finally made available in June 2022.
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Download The Bugs Bunny Birthday Blowout (prototype)
File: The_Bugs_Bunny_Birthday_Blowout_(Prototype).zip (96 KB) (info)
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Contents
Sub-Pages
Stage 1 The most complete stage, but that's not saying much. |
Stage 2 The obligatory desert stage. |
Stage 3 The volcanic stage. Watch out for lava! |
General Differences
- There are no copyright, title, or story screens. The game throws the player to Stage 1-1 immediately.
- All objects, including Bugs, move at about half the speed they do in the final. This also means that the floating platforms have their ranges halved, making some sections impossible to cross.
- There are no giant carrot objects present, meaning levels cannot be completed. The code for the object is present and partially functional: touching it will cause Bugs to float off the screen in a balloon as in the final version, but the level still doesn't end, and the music loops indefinitely.
- There is no lives system, so it's not possible to get a Game Over. Code-wise, the basic framework for the system is in place, but it is hard-coded to jump to the same code path regardless of the life counter's value.
- Carrot icons do not make a sound when collected.
- Powerup icons do not make a sound or disappear when collected, though they do still set their corresponding flags at $430 in RAM:
- Speed up (01): This functions as a high jump in the final game.
- Hammer (02): This would kill more powerful enemies and bosses in one hit, if there were any to actually use it against.
- Unknown (04): This was replaced with the heart in the final game (see below). There is no code in either the prototype or final game that reads its associated flag, so its intended functionality is unknown.
- Powerup flags are not reset after taking damage or losing a life.
- Crumbling rock platforms are marked with different palettes to identify their type (delayed or immediate).
- Bugs does not dive in and out of tunnels. The tunnels behave much more like the pipes in Super Mario Bros.
- There are four debugging functions available: hold Start when starting the game to get a stage select menu, B to start on Stage 2-2, or A to go to a preliminary version of the Mole Game. You can also moonjump by pressing Select.
- The Mole Game is more of a graphical demo than an actual game at this point. The moles cannot be hit, Bugs' sprites are glitched (due to a mismatch between his tilemap and the actual CHR layout), and both the music and the game loop indefinitely. It is possible to "end" the game before it starts (triggering the otherwise unused messages "CARROT IS SHORT" / "SEE YOU AGAIN.") by freezing the carrot counter at 0, though it is programmed to simply restart from the beginning when this happens.
- All of the music tracks used in the final game are present and complete, though a good number of them are unused at this point in development.
Graphical Differences
General
For graphics that appear in multiple levels.
Proto | Final |
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The disappearing platform in the final was a more complicated spinning platform at this point. The design was simplified to make room for Bugs' diving animation, but while the platform "disappears" it still spins, so if you were ever wondering why those platforms had weird collision...now you know.
Proto | Final |
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The graphics of Bugs and the balloon's basket were improved for the final.
Proto | Final |
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The heart was originally a bunny head next to some odd-looking waves in the prototype. This item sets a flag in RAM in both the prototype and final versions, but no code seems to actually read it; it's possible the item originally served a different purpose, and the heart functionality was tacked on later in development.
Proto | Final |
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The alarm clock is a bomb in this build. Same function, though, and the clock makes more sense thematically.
Proto | Final |
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Elmer's nets were given more detail in the final.
Title Screen
Proto | Final |
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Although the prototype normally bypasses the title screen, it is present in the ROM and can be seen by changing ROM address 0x1E752 to $40 and holding A as you power on/reset the game.
At this point, the chains are larger, the letters of the title have some shading that was removed in the final, and there are little squares around the border.
Mole Game
Proto | Final |
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The Mole Game has actual moles in the prototype. The final instead uses Willy the Weasel.
Proto | Final |
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This change altered the title graphics as well, replacing the unique graphics of the prototype with a rather plain-looking text box in the final.
Level 4
Proto | Final |
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The pipes in this stage are thinner in the prototype.
Level 5
Proto | Final |
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The tileset for Level 5 is seemingly older than the rest, as it does not yet contain any powerup icons, only a single carrot graphic in a completely different style from the final icons. This was likely changed because, being a background object, it could not be placed on anything but an empty sky background without creating a big ugly hole.
Proto | Final |
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The inclusion of powerup icons meant that some graphics had to be removed, so the second tile for the tree trunks in the prototype was overwritten in the final. The trunk was also given some additional shading.
Proto | Final |
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Another victim of tile overwriting: the unique spike graphics were changed to the simpler 8×16 ones used in other levels.
Level 6
Proto | Final |
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The lip of the vase was changed slightly in the final.
Proto | Final |
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The (American) football was redrawn to look more like a...well, football.
Ending
There's no ending in the prototype, but the graphics are there.
Proto | Final |
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Bugs' eyes were redrawn to remove the cross-eyed look of the prototype.
Proto | Final |
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And again.
Proto | Final |
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Road Runner and Pussyfoot were removed from the photo in the final, probably because they don't actually show up anywhere in the game. Taz's oddly-proportioned stomach was fixed in the final.
Unused Graphics
Graphics that are mostly absent from the final.
Mole Game
Various tiles from the Mole Game. Most of these are still present in the final version, with only the normal mole head and the first three letters of "SORRY" having been removed.
Speedy Gonzales
Yep, it's him. His sprite only appears in the prototype, though there doesn't seem to be an object associated with these graphics.
Spiked Ball
Just a simple spiked ball.
???
These odd tiles take up a character bank in the prototype. It's unknown what they would have been used for, or if they were even intended for this game, though it's possible that the letters were originally intended to be powerup icons before the final icons were implemented as background objects. These were replaced with the Game Over and copyright tiles in the final.
Audio Differences
Music
There's an extra piece of music in the prototype which is used while Bugs walks into frame. Normally, this cuts off after about one second, but the rest can be heard by changing ROM address 0x1950B to $60.
Proto | |
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Final |
The death jingle is 20% faster in the final.
Proto | |
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Final |
The World 3 song has a 2.5-second intro which was removed from the final track.
Proto | |
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Final |
The bonus stage song is about five seconds longer than the final, and has a different ending.
Sound
Proto | |
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Final |
Bugs' hammer sound in the final has a second pulse channel component, which is not the case in the prototype.