The module files in Super Smash Bros. Brawl are located in the module folder. All fighters and stages have these files, which have the suffix .rel. For example, st_donkey.rel is the file for 75m.

Editing stage .rel files (of course)Edit

You will need a hex editor.
Open the stage module file (of the format st_XXXX.rel) for the stage you want to replace something with. Let's say you want to replace Flat Zone 2 with a stage based on Final Destination. Each module file has a sequence of bytes somewhere in the file that goes like this:

38 A5 00 00 38 80 00 XX

The value of XX is the ID number of the stage, taken from this list:

STCUSTOM (Phantom Wings' code)	00	st_custom[1-9].rel
Battlefield			01	st_battle.rel
Final Destination		02	st_final.rel
Delfino Plaza			03      st_dolpic.rel
Luigi's Mansion			04      st_mansion.rel
Mushroomy Kingdom		05      st_mariopast.rel
Mario Circuit			06      st_kart.rel
75 m				07	st_donkey.rel
Rumble Falls			08	st_jungle.rel
Pirate Ship			09      st_pirates.rel
Norfair				0B      st_norfair.rel
Frigate Orpheon			0C      st_orpheon.rel
Yoshi's Island (Brawl)		0D      st_crayon.rel
Halberd				0E      st_halberd.rel
Lylat Cruise			13	st_starfox.rel
Pokémon Stadium 2		14      st_stadium.rel
Spear Pillar			15      st_tengan.rel
Port Town Aero Dive		16      st_fzero.rel
Summit				17	st_ice.rel
Flat Zone 2			18	st_gw.rel
Castle Siege			19	st_emblem.rel
WarioWare Inc.			1C	st_madein.rel
Distant Planet			1D      st_earth.rel
Skyworld			1E      st_palutena.rel
Mario Bros.			1F	st_famicom.rel
New Pork City			20	st_newpork.rel
Smashville			21      st_village.rel
Shadow Moses Island		22      st_metalgear.rel
Green Hill Zone			23      st_greenhill.rel
PictoChat			24      st_pictchat.rel
Hanenbow			25	st_plankton.rel
ConfigTest			26      st_config.rel
Result				28
Temple				29	st_dxshrine.rel
Yoshi's Island (Melee)		2A	st_dxyorster.rel
Jungle Japes			2B	st_dxgarden.rel
Onett				2C	st_dxonett.rel
Green Greens			2D	st_dxgreens.rel
Pokémon Stadium			2E	st_dxpstadium.rel
Rainbow Cruise			2F	st_dxrcruise.rel
Corneria			30	st_dxcorneria.rel
Big Blue			31	st_dxbigblue.rel
Brinstar			32	st_dxzebes.rel
Bridge of Eldin			33      st_oldin.rel
Homerun				34      st_homerun.rel
Edit				35      st_stageedit.rel
Heal				36      st_heal.rel
OnlineTraining			37	st_otrain.rel
TargetBreak			38      st_tbreak.rel

So in the example, you would want to open st_final.rel search for:

38 A5 00 00 38 80 00 02

You want to replace the XX value with that of the stage you want to replace. So change the string to:

38 A5 00 00 38 80 00 18

Save the file as st_gw.rel. Now you should be able to put a Final Destination-based stage over stages/melee/STGGW.PAC.

For custom stages using Phantom Wings' Custom SSS code, the XX value you should enter is 00.

Also, Smash World Forums user Bero has given us a tool to easily make .rels!

A .rel file to use an OnlineTraining-based stage as a custom stage with Phantom Wings' code can be found here: In this file, XX is 00, but you can change it with the method above if you want it to replace a stage already in the game. This .rel file is verified to have no Sandbag. (as far as I know, this is something that PW changed in the .rel, but I might be wrong --User:Libertyernie)

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