Source:
https://rpgmaker.net/games/2015/
Creators:
GreatRedSpirit
Anaryu
ankylo
arcan
captainregal
D-Bones
Dudesoft
Gigabowser
Karsuman
kentona
Little Wing Guy
Magi
Max McGee
Ratty524
Shinan
Solitayre
uh
VideoWizard
ShortStar
WIP
Publisher:
GreatRedSpirit
Files:
Super RMN Bros v1.2=Super RMN Bros.7z
Super RMN Bros REMIX by Shortstar=Super RMN Bros - REMIX.zip

Description:
Super RMN Bros. is a community event where everybody tries to make 2D Mario platformer levels and they all get put into one game: Super RMN Bros! The tool used for this is Super Mario Bros. X v1.2 Beta4 (SMBX), a PC Engine made to emulate the Mario games made on the NES and SNES. This event is to let everybody try out this new tool and see what we can make in two weeks in a genre everybody has played! Whip out those old Mario level drawing you made when you were eight! Live the dream of making your own Mario game! Show that RMNers can do more than just make RPGS!

What You Need to Play Super RMN Bros
SMBX doesn't distribute standalone games: You'll need the full package to play Super RMN Bros. Download Super Mario Bros. X v1.2.1, available at the bottom of the OP in the link. Extract it into your favorite games folder, download Super RMN Bros. and put it in its own folder in the 'worlds' folder in SMBX. Start SMBX and select Super RMN Bros and start playing!

All The Levels
Check the gameprofile navigation!