Now I know to hack level layout in both ROM and savestates, and I discovered one of the most bizarre programming holes in S2 SMS.
After reviewing, by normal gameplay, all levels of S2, I realized there are no bottomless pits at all. There are spikes everywhere they should be, even in Sky High Zone.
See, as example, this hacked savestate of Gimmick Mt. act 1. I remove all standard solid blocks from layout. If you fall to the bottom of the screen, you will find a surprise.
Note: This package includes two savestates, ".s00" for MEKA and ".ss0" for Fusion. Savestates will only work if your ROM is named "Sonic the Hedgehog 2.sms".
Number of downloads: 5