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An Sprite Insertion Tool For SMW


This is a tool for inserting sprites into Super Mario World ROM image.



Lunar Magic version 1.65 or higher.

When using the exita bytes feature, version 1.80 or higher is required.

Compatibility with other tools


I haven’t checked anything other than these. Other than the tools listed here may work.


You can’t use these tools together.
It is NOT incompatible with sprite files.



How to use

File formats

Sprite coding information


Technical information


DLL Error

dll error

It seems that some of the files are broken. Please try downloading again.


In the first use, the following error may be output in some cases.

E:\giepy_v1.00\asm\include\ (called from E:\giepy_v1.00\asm\giepy/load.asm:68): error: Assertion failed [assert $90e7c9 == read3($02a866)]
E:\giepy_v1.00\asm\include\ (called from E:\giepy_v1.00\asm\giepy/normspr.asm:19): error: Assertion failed [assert $08a9 == read2($018172)]
E:\giepy_v1.00\asm\include\ (called from E:\giepy_v1.00\asm\giepy/normspr.asm:19): error: Assertion failed [assert $c89d == read2($018172+2)]
E:\giepy_v1.00\asm\include\ (called from E:\giepy_v1.00\asm\giepy/tweaks.asm:13): error: Assertion failed [assert $9d14 == read2($01c089+2)]
Assembling of "E:\giepy_v1.00\asm\giepy.asm" failed...

In this case, some tools or patches are in conflict.
Uninstall conflicting tools.

Sprite not found

CFG file "scroller/l2_onoff_scr.json" was not found in the search path.
Failed to load the CFG file "scroller/l2_onoff_scr.json"...

There are multiple causes to consider.

  1. Specifying an incorrect sprite directory
    Correct sprites directory specification.

  2. Incorrect specification of list
    Collect the list file.

Label not found

E:\giepy_v1.00\sprites\scroller\l2_onoff_scr.asm:75: error: Label UpdateLayerPos not found [jsl UpdateLayerPos]
Assembling of "E:\giepy_v1.00\sprites\scroller\l2_onoff_scr.asm" failed...
CFG file "E:\giepy_v1.00\sprites\scroller/l2_onoff_scr.json" processing failed...

There are multiple causes to consider.

  1. Wrong library directory specification
    Correct library directory specification.

  2. Incorrect routine name
    Correct sprite ‘s asm file.


License of GIEPY is MIT license.

And GIEPY is using these libraries and softwares.

Library Copylight License
Asar ©Alcaro, p4plus2, Raidenthequick and RPGHacker LGPLv3
TRASM ©1994 Norman Yen AKA 1000 Miles [Tricks] PUBLIC DOMAIN
Jansson ©2009-2016 Petri Lehtinen MIT
bolib ©2017-2018 boldowa MIT

Referenced projects

I referred to the following projects and sites.

Name Copylight License
PIXI ©JackTheSpades  
Romi’s Spritetool - v1.41 ©mikeyk, Romi  
Daiyousei ©Katrina  
Tessera, v. 0.52 (imamelia’s Sprite Tool) ©imamelia  
MeiMei ©Amaterasite  
VilelaBot ©Vitor Vilela  
SMWCentral ©2005-2018 SMW Central  

Also, I would like to express my gratitude to everyone who reported bugs and advice at Twitter and Discord.

  1. Only LoROM is supported.  2