The Second Episode. World F. F-1 has a section in the clouds, F-2 is an 8-1-ish level, F-3 is a treetop level with short platforms and F-4 is a castle, reused from 6-4 from Jeansowaty Levels (version 2.0). The level was bugging out so Jeansowaty Levels got a new 6-4, while the old one was polished and became F-4 now :) Enjoy!
Database match: Super Mario Bros. (World)
Database: No-Intro: Nintendo Entertainment System (v. 20180803-121122)
File SHA-1: EA343F4E445A9050D4B4FBAC2C77D0693B1D0922
File CRC32: 3337EC46
ROM SHA-1: FACEE9C577A5262DBE33AC4930BB0B58C8C037F7
ROM CRC32: D445F698