FDS Super Mario Bros. 2, 1-2 clip notes

Table of Contents

Introduction

The 1-2 clip, commonly known as “1-2 Blazit”, is a trick performed in high-level Super Mario Bros.: The Lost Levels submissions. This wall clip bypasses the need to hit the two invisible coin blocks near the area's end, saving anywhere from 1.4 to 2.1 seconds over a fast climb. Various methods for performing the wall clip have been discovered and documented to save time with the clip, with varying degrees of difficulty.

This page aims to provide detailed documentation for the 1-2 clip with various resources including example video, FM2 input files and data visualisation to provide a means for runners to understand each method.

Please note that all FM2 files provided are for the 6.0 Beta release of the “Pellsson” practice ROM, please download the BPS patch here: Download Link

Safe Strategy

This safe strategy for performing the 1-2 clip was documented originally by user “Nobodycallsmetubby” on YouTube [1] and saves 1.4 seconds over a fast climb. This method involves landing on the first row of question blocks at the start of the area on the first possible frame to lose the appropriate number of subpixels.

If a runner wishes to know if they successfully landed on the first possible frame while practicing within a practice ROM, the subpixel digit left to the static 0 must alternate between F and 7.

This chart [2] provides a visual representation of the correlation between the duration A is held, and the frame a runner jumps on. As seen by this data, it is preferred to jump later because of a greater window to land on the first possible frame.

Once you are set up for the clip, the next important factor to consider is the jump into the wall. There are multiple frames you can jump from the ground.

The A-press durations listed can get you set up for only requiring 1 jump to fully enter the wall.

While jumping, you want to release right while mid-air to pause your subspeed value. You want to ideally release right on any value from 0 up to 140 subspeed. Subspeed values from 144 to 196 can work, however, they risk potentially pushing you out of the wall immediately depending on when you start holding left. Avoid 228 to 252 subspeed, because you will immediately get pushed out if you hold left on the last frame possible.

You generally will have a 3-frame window to start holding left to enter the wall, sometimes it can be a 4-frame window depending on your subspeed. However, holding left earlier can make it difficult to get reliable wall clips and can make clipping into the wall with only 1 jump impossible.

Once in the wall, you should aim to re-press right as soon as possible. This is because while you are in the wall with 0 speed, Mario will move further to the right without scrolling the screen and that will make it harder to quickly load the scroll stop for the “WELCOME TO WARP ZONE” message. Failing to load this message will result in Mario being sent to the bonus room rather than World 4-1.

When attempting to exit the wall, you have a 3-frame window to face the other direction and jump out of the block. Once you are out of the block you should aim to land on the ground as early as possible while missing the pipe to reset Mario’s speed to 0 as fast as possible. You should also aim to get close to the pipe by holding left while descending to the ground, but not close enough to accidentally bonk the pipe while attempting to enter the pipe.

Sample Video:

Link to FM2 File: Download link to sample 1-2 Safe Setup FM2

Sockfolder Input Strategies

Coming soon

Sample Videos:

Link to FM2 Files:

Down+Right Strategy

Coming soon

Sample Video:

Link to FM2 File: Download link to sample 1-2 Down+Right Setup FM2

References

[1] Nobodycallsmetubby, “1-2 clip smb2j ‘safe strat,’” YouTube, Dec. 15, 2018. https://www.youtube.com/watch?v=bB0Z_NIkVdQ

[2] Simplistic6502, “1-2 Walking Clip,” Google Docs, Jan 29, 2025. https://docs.google.com/spreadsheets/d/1X1p4-y8mdVy17HxJyMudZRxjFKS043GFQ9PwoZrkpxI/edit?gid=0#gid=0