LAAAAAAAYLAAA!! [slide guitar solo]
In this game, not-the-Dirty Pair fly around the galaxy collecting heavy weaponry, blowing apart asteroids, and not being the Dirty Pair. (Perhaps they couldn't get the license for some reason?) Imagine if Super Mario Bros. had guns, and if every warp pipe led to a completely random part of the level, and if the levels were really goddamn massive.
The sprite graphics set for the bonus rounds seems to have been copied from a work-in-progress version of another graphics bank and only modified as needed. As a result, it contains unused earlier versions of quite a few sprites from the main game.
Layla and Iris
The most notable difference between the early and final sprites is Layla's hairstyle, which gained more distinctive bangs in the final. The early sprites also lack the highlights on the boots to distinguish the near foot from the far.
The pistol/machine gun's shot is two pixels wider in the early graphics.
The grenade was redrawn for the final. It's almost but not quite a horizontal flip of the early graphic.
The tip of the fireball's tail was shifted up in the final, for whatever reason. The early graphic is actually used for the shots fired by the space motorcycle...thing in the bonus game.
The bazooka's shot was completely redrawn.
The projectile fired by certain enemies was enlarged and recolored in the final.
- In the prototype graphics, Iris' tiles are scattered around chaotically and would have required a lookup table to be correctly "patched" onto Layla's graphic mappings. In an effort to simplify the code, the final version rearranges things so that Iris' tiles are all a constant distance from the Layla tiles they replace, allowing this to be done with a simple addition operation.
- The graphics for the ice cream cone health pickup and the keycard are blank in the early set, indicating those items didn't exist or hadn't been implemented at the time it was made.
The ending theme fades out after about forty seconds, but the full track runs to a whopping minute and forty-five seconds! The full version is present on the NSF rip, and can be heard in-game by activating the cheats 0011:FF and 008F:FF during the pause between Manitokha's message and the staff credits.
"Dual Iris" Mode
The game contains unused code for having two "helper characters" simultaneously instead of just one. RAM $046A controls whether Iris is disabled (zero) or enabled (nonzero), but if it is set to exactly 0x3D (patch code 046A:3D), the game activates a "third character" in addition to Layla and Iris. This character looks like and behaves identically to Iris, firing extra shots to complement Layla's, but follows Layla on a shorter delay than the "real" Iris (and usually flickers nonstop due to sprite limitations).
By accident or design, this mode sextuples the amount of ammo used by weapons instead of just tripling it, so don't expect to be able to use it for long with anything except the infinite-ammo pistol. It doesn't really matter anyway, since with this activated even the pistol can tear through most obstacles in a single button press. Speculatively, this might have been used for a limited-time power-up (perhaps in place of the special weapon's default "give 1000 points and do nothing else" mode).
This most likely went unused in the final game because the very large number of sprites used by the third character and her shots causes severe flickering and screen "jumpiness". (The fact that the game basically rolls over and dies if it hits the NES's 64-sprite limit may also have been a factor.)
Certain portions of the game's code suggest that it was originally supposed to be possible to scroll the screen left instead of only right. During gameplay, when the game decides whether or not the screen needs to be scrolled, it first checks bit 0 of RAM $001D. If it is not set (which is normally always the case), and Layla is facing right and has a screen x-position of 0x90 or greater, then the screen scrolls to the right.
If bit 0 of $001D is set, though, the game instead checks if Layla is facing left and her screen x-position is 0x60 or less, and proceeds to the scrolling update code if so. Then at 0x01EF92, just before the actual scroll is performed, the game checks if Layla is facing right and branches to the right-scrolling code if she is. Presumably the code for left scrolling is supposed to follow, but there isn't any—the branch has a distance of zero, a strong indicator that the code was removed or (more likely) never implemented. The net result is that the screen always scrolls right, even if all the other left-scrolling conditions are met.
Alternate Spawn Mode
The game contains some code at 0x1DF9B for an alternate method of spawning objects. This code is mostly functional and will activate if bit 5 of a spawn specifier's first byte is set, but no specifier in the game does this.
For "normal" spawns, the game simply reads the object's type and creates it. In the alternate "expanded" mode, the game reads an extra byte that specifies the number of objects of this type to spawn (up to four simultaneously) and their initial y-position (which is normally set by the spawned object's initialization code).
Due to a programming error, this code often writes the object data to the wrong object slot, often causing an existing object to vanish when the new one is spawned. It may have been scrapped for this reason, or perhaps it was dropped for unrelated reasons before the code was fully debugged.
Curiously, every level's object definitions are specially set up to allow the "trapped Iris" object to be placed, meaning it can theoretically appear in any level even though it's only needed for level 5. It's possible Iris's location wasn't decided on until later in development.
The game has twelve special passwords that start the game from certain hardcoded configurations.
|Password||Pistol||Machine Gun||Grenade||Flamethrower||Axe||Bazooka||Beam Saber||Barrier||?||Skates||Level||Keys||Iris|
|147147147147147147||1||0||147||0||147||0||147||0||0||1||1||1, 4, 7||N|
Most of the passwords seem to be references to developers, the game itself, or bits of Japanese pop culture:
|ONOMATSUNONAKAJIMA||N/A||The names of some of the game's developers: director/programmer Hiroshi Ono, director Seiichi Matsuno and/or graphic designer Backy Matsuno, and programmer Yukiharu Nakajima.|
|AHK0TINAMS1RIALYAL||Layla Iris Manitokha||The names of the game's protagonists and antagonist, written backwards and with numbers substituted for some letters.|
|MANTOINUMONKUNEKOO||Manto the Dog, Monku the Cat||Manto and Monku were mascot characters for the now-defunct Japanese gaming magazine Marukatsu Famicom.|
|KAKUSHIKOMANDODAZO||It's the hidden command!|
|NUKENINHAVOLGUARD2||Volguard II is a fugitive ninja||Refers to Volguard II, another game by dB-SOFT.|
|OPUSYONHAIRISDESU0||Iris is an option/With an option||Presumably using the term in the Gradius sense of "thing that follows you and shoots extra bullets," which sums up Iris' role in the game. Note that this password unlocks Iris from the start of the game, which isn't normally possible. The password actually has two possible interpretations as written: "Iris is an option" and "With an option".|
|CAKEICERINGOKOHRII||Cake, Ice, Apples, Ice||Refers to the game's health-restoring items.|
|MUTEKIKAMOSHIRENAI||Might be invincible|
|MAHOUTUKAISARINANO||I'm Sally the witch!||Refers to the 1966 manga/anime Mahou Tsukai Sally/Sally the Witch, the first magical girl series.|
|IRUKIBOMOTIHONODNI||Indians are surprised too||Another backwards message; read the proper way, it's a minor variation on インド人もびっくり, the tagline from a 1964 commercial for S&B Foods curry that's somewhat fondly remembered in Japan.|
There's a ton of unused data at the end of bank 2 which isn't a duplicate of data elsewhere in the ROM (unlike the rest of the game's ROM filler). Is there anything interesting in there, or is it just garbage?