One of the comments says that the matching ROM image (MD5: ee0424cf1523f67c5007566aed70696d) is listed in GoodGBx as "Zelda no Densetsu – Yume no Miru Shima DX (J) (V1.0) [C][p1][T+Chi][!].gbc", and that the original ROM doesn't have it. That would explain the CALL patching.
Ninja'd, but in particular, according to these two, the GoodTools codes in that filename indicate that it's a pirate Chinese ROM translation. Yes I know I'm getting off-topic
Can we talk about the gameplay implications here, though? The isometric maps in Crackers aren't something I've ever seen discussed at length, actually- my personal theory had always been that they were going to be an overworld for selecting stages like what Lost World eventually got, given how little indication there is to how these sections would've played (the factory stage at least has tiles for a springboard, so we know aerial movement was planned). But now that we have action sprites, we know for sure that a second full-fledged gametype was planned. What's weird is that the stages are isometric, but there are no diagonal sprites for the players. Doesn't seem like there was much coordination going on with the team at this stage of development. Also I love the cast shadows in that "victory" animation.
Yes, but reusing ideas from one project in another, even when entirely unrelated teams are involved, is hardly unheard of in the Sonic series. Ristar shares no staff between Sonic 1, Sonic 2, and Sonic 3, yet is generally agreed to have evolved from the original concept from Sonic 1. Consider, also, that during roughly a 3 year stretch (1993-1996), there were at one point 5 different attempts at an isometric Sonic game (SegaSonic Arcade, Sonic Mars, Sonic 3D Blast, Sonic Labyrinth, and Sonic Crackers). Clearly this was an idea they kept bouncing around. EDIT: Only big wrench is that the Sonic Mars pitch was May of 1994, where the Crackers Prototype we have is from April of 1994. But the pitch for Sonic Mars in May of 1994 was not the isometric Mars, but rather the one based off of the Amiga animation. The isometric Sonic pitch that Senn produced (the image above) isn't dated.
Dimps often recycled scrapped ideas. I wonder if Terminal Velocity in Sonic Colours DS was inspired by these scrapped over head stages in Sonic Crackers. Also, Sonic 3 was originally supposed to be an isometric game and at one point they were going to use the SVP chip, but it wouldn't have been ready in time for the release. Perhaps some of these scrapped ideas influenced the stage.
This data is an interesting find. If we have a modern who can hack into sonic crackers and insert and sprites from that prototype and the unused data, we could see a rom hack of Knuckles Chaotix with sonic and tails with the sonic crackers sprites instead of custom sprites. That would be interesting to see that happen.
I thought I might share some information on the fields since you're all talking about it, perhaps it'll help to trigger some ideas or information about them. First of all, these fields are not isometric perspective, they are Cavalier perspective, which is why: The LZSS crackers decompression algorithm subroutine (which was used for the SEGA screen and the field art), is located directly after the fields, and is nowhere near the SEGA logo, which indicates the compression was likely introduced along with the fields. The mappings are fixed (as in, there is no level layout structure applied, it is just a simple map and art set written), they are also left uncompressed, it is safe to say that it's merely a placeholder (likely the compression is a placeholder too). The fields have their own specific pause subroutine, as well as their own player control, and object running routines, in fact, almost everything about the fields are unique and local to it. If the rest of the game was ripped out, these stages would nearly survive on their own without support. There are no arrays for the two stages currently for the fields, it is very strictly a basic comparison of the Zone ID in RAM, further indicating the code is all temporary, and will probably be scrapped in favour of something solid later. Even though the character list has an array and 8 reserved slots, of which two are used (for Sonic & Tails). So they put the effort into an array for the characters, but not the field stages. Some things regarding the VDP settings: Shadow and highlighting is turned on, so they may have planned some use for that. The plane size has been set to 512x512 (this is unusual for Sonic games, since they usually fix themselves to a 512x256, except for special stages or the like), this one is curious, because no-one in their right mind would use a large plane size like this, unless they were simply meant to load a fixed set of mappings that did not get redrawn. If they wanted to realtime render a larger level, they probably would have used the 512x256 size instead to save on VRAM, but this contradicts the fact that these levels "feel" like they should be larger, especially with that springboard.
Showoff :P All this makes it sound like these fields were pretty hastily bolted on, perhaps it was at one point an entirely different project? Maybe separate pitches, or they hadn't nailed down the direction they wanted to go in? Perhaps they intended to do some vscroll trickery to play off the perspective?
So has anybody tried grep-searching for a piece of the crackers graphics to see if they're in any other "overdumped" prototypes that we know of?