Kaizo Mario Bros. 3 is a ROM hack created by the late Obitus1 designed to challenge the most skilled Super Mario Bros. 3 players, just like the Kaizo Mario World games are designed to challenge the most skilled SMW players (we have a published run of the third iteration right here).
Naturally, Lord_Tom forgoes most of the challenges proposed in this hack and showcases some interesting strategies for beating the 22 levels in record time.
The official encodes feature commentary by the author as soft subtitles.