Econo is an SMB3 Kaizo Hack, with an intended difficulty of “intermediate.” It was made using a USA Rev1 version of SMB3. You can download the hack and access the readme here: https://bin.smwcentral.net/u/62356/Econo%2Bv1%2B11.13.23%2Bzip%2Bfile.zip
And here's a link to the romhacking.net page for the hack: https://www.romhacking.net/hacks/8220/
Special thanks to the following people who directly contributed to the hack.
WilsonPenn: Many integral patches, custom asm, asm support and debugging help, and general inspiration from his hack “Git Up Git Out Git Gud.”
GrumpyJake: The first person to playtest the whole hack, and the person who had to deal with the worst of the jank.
BlueFinch: Patches, custom asm, and playtesting.
Kurbo: Playtesting.
MitchFlowerPower: Playtesting.
JoeSmo: Creating the SMB3 foundry creation tool and making a key patch.
MaCobra52: Very many patches.
or4ng33xp0: Patches.
Captain Southbird: SMB3 disassembly.
Loop_Hazard: Music in the hack trailer.