As awesome as this particular variant of Butter Building was (and honestly, Butter Building feels like a cool concept for a stage anyway), there is actually an issue I have with it in a 2D platfighter context; and to explain it, I'll throw together a diagram real quick.
The problem that occurs to me is mostly with animation; what with the stage's base being circular, it means that you kind of run into issues with how exactly you handle ledge-grabs. See, from a purely 2D perspective, you could make the argument that you could go all the way to the apparent "edge" of the platform; but doing that would have a few issues.
In this case, presume the red line is the actual "field of play" - that is, the 2D plane within 3D space where all the fighters are. The "edge" of the platform (given it's circular) would be represented with the orange point; but the "apparent edge" I referred to earlier would actually be all the way up where that green point is, pretty far back in the stage's background.
This works fine enough in a purely 2D context like a sprite-based game (such as
SSF2 for example), and works just fine in
Kirby Fighters 2 because - as you mentioned - the stages are all walled-in. The problem in this particular scenario is that you'd have to work out a way to make it so that character's ledge-grab animations keep to the red line, but as a result, make it so they don't clip into the stage when they're holding onto the side.
This wouldn't be an
impossible fix; there's four ways that spring to my mind;
- A visual gimmick/element loosely akin to the Mario Galaxy stage, whereby characters visibly move into the background a little due to the line of play being physically altered (akin to the green line), but this would run into a ton of issues of visibility.
- Featuring two additional, entirely unique ledge-grab animations (and possibly animations for things like ledge-hops, ledge attacks, etc) for characters to exclusively use on Butter Building. Seems like a ton of work for just one stage.
- Redesigning the stage itself to make the ledges more appropriate for the general-purpose animations. Plausible, but you wouldn't want to lose too much of the stage's visual identity in the process.
- Having Butter Building, which is specifically well-suited to inclusion because it's high above the ground, as a run-off stage that doesn't have lower blast zones. (This kind of defeats the object of including Butter Building in the first place.)
Idk. I've always been a fan of Butter Building but it seems like it'd be a lot of work.
