Here's all the levels, sorted by creator:

Anaryu
- Mediocre Central
- Skyjinx

Ankylo
- Ankle Biter Forest Forest
- Ylo Bro! RMN Bros

Arcan
- Lava Underground

calunio
- Trap Jumps
- RMN Trip

CaptainRegal
- A Very Regal Mario

D-Bones
- Grassland
- Cliffside
- Highup
- BobOmb Battlefield
- Bowser Road

Dudesoft
- Lazy Lake
- Bob-omb Facility

Gigabowser
- Giga Underground Way

GreatRedSpirit
- Precarious Platforms
- Break Bowser's Blockade

Karsuman
- Pipe Dreams

Kentona
- Kentario
- Kentaro Desert
- Kentonee Floodplains
- Kentsnowna

Little Wing Guy
- Pirahna Plant Mountain

Magi
- Saguaro Samba
- Road to the Fortress

Max McGee
- Max McGee's Wild Ride
- Fairway
- The Castle Aaaaaagghh
- Arcophobia

Ratty524
- Wild Climb
- Cavern Calamity

Shinan
- Gazelle Steppe
- Underground Run

Solitayre
- Blasting Zone
- Jungle Fever
- Pirahna Palace
- Dark Kingdom

uh
- Pampers

VideoWizard
- 1-1
- Lava Locks
- Snowy Plains

WIP
- Fairbreeze Lake