Gatoslip now has S&K lock-on features
For awhile I knew that S&K checked for the attached cartridge's header to execute it's code, but little did I know just how far one could go beyond just allowing a full version of Blue Spheres...
For this in particular, I put a dummy Sonic 2 header around the 3MB mark (game is too large and won't mirror) and exploit the fact it uses Sonic 2's Sound Driver loading routine by having code that hijacks the gamemode address table and runs its own code on top.
And I can go further than just a simple mock scene before Blue Spheres :
When you fit S2 into S&K, you get KtEiS2
When you fit Gatoslip into S&K, you get P&K