File replacement is a general term used to describe replacing various elements of a video game like textures, sounds, music and movesets.
File replacements are quite common in the Super Smash Bros. series. Initially holding niche appeal amongst gamers, improvements to the hacking scene, especially for Brawl, have led to more and more sophisticated file replacement hacks for the games. A majority of game mods for the games feature extensive use of file replacement hacks in order to deliver a unique experience to the mod.
File replacement in Smash 64 is accomplished by the use of the Rice Video plugin in conjunction with an emulator. The lesser fanbase of Smash 64 is the primary reason why this type of file replacement is less common than for the other games; additionally, Rice Video has been implicated in causing stability problems with Super Smash Bros. with certain hardware and emulators
Owing to an inability to design cartridges for the Nintendo 64, no effective way has been found to replace files and use the modified ROM on an actual console.
Largely untouched for the first nine years since the game's release, file replacement in Melee gained popularity when S. of Stack Smash posted his texture hacks online. This process entails replacing files directly to the ISO with a program such as GC-Tool, and then burning the ISO to a disc or saving the ISO on a computer so that it can be run with an emulator such as Dolphin.
Due to the difficulty in hacking the GameCube console by itself, the difficulty in reliably accessing the Wii's RAM for playing GameCube games, and the steep system requirements of Dolphin, file replacement in Melee is considerably less widespread than that for Brawl, though it does have a few devoted developers. Improvements in Dolphin itself have allowed for more hacks to be produced for the game, with Melee: SD Remix featuring numerous changes to the game's stages and character movesets via file replacement. With that in mind, more advanced modifications (like model replacement, new animations, and so on) have only very recently been made for Melee, compared to its successors receiving the same treatment within a few years of release.
Due to the ease of hacking the Wii through the use of the Homebrew Channel, the lack of technical expertise in getting the Homebrew Channel and replacement files, the ability to hack a Wii because of the Smash Stack exploit, and a wide variety of resources available for it, file replacement is the most popular in the Brawl community, with many websites available solely for downloading a variety of hacks for the game. Brawl hacks are also known for being the most sophisticated of any Smash game, with all-new character movesets and unique stages even being introduced to some mods; programs like BrawlBox and Open SA also exist to assist in the creation of file replacement hacks.
Brawl hacking was initially restricted to particularly devoted players, as hacking the game's files initially required the extensive use of modified ISOs and Wii consoles in order to run hacked data. Hacker Phantom Wings is credited to expanding the popularity of Brawl file replacement hacks, as he made file replacement available to users using SD cards, with most prior file replacement hacks requiring hacking of the Brawl ISO itself.
File replacement returns in both Super Smash Bros. for Nintendo 3DS and Super Smash Bros. for Wii U. Though somewhat more difficult to access compared to Smash Stack, due to the improved security of the two consoles, several mods have been made for each game, with the ability to use assets between them due to sharing the same file formats. Both games use a "Layered File System", or LayeredFS, implementation to run modded files loaded onto an SD card. With the advent of game updates, mods must be specifically compiled for the version of the game that is being edited.
Texture and vertex hacking (eg. a "Jumpman" costume for Mario and the Fusion Suit for Samus), model replacement via importing (Chrom or Magnus over Ike) and costume addition (eg. an extra costume slot for a White Yoshi costume) return.
The ability to edit a character's moveset returns, ranging from a character's attributes to their animations.
Other cosmetics such as selection portraits, names, fonts and menu backgrounds can also be changed as well.
There are some new additions to file replacement in Super Smash Bros. 4, which include:
Smash 4 modding, like with Brawl, is perhaps equally popular. All the new aforementioned additions to modding have been demonstrated on GameBanana, a website which is similar to Brawl Vault.
Like the previous game, Ultimate file replacement relies on LayeredFS and mods placed on an SD card. At the current moment, only consoles released prior to July 2018, which contain a bug in their bootloader allowing users to make runtime patches to the console's operating system, are capable of running mods. Due to the bulk of the game's assets being contained within a single, multi gigabyte file, thereby requiring the file in its entirety to be replaced for conventional file replacement to work, mod files are labelled with pointers to what they are intended to replace.
So far, hackers have been able to replace the game's textures, UI elements, and music.
Each hack varies from one to another. Either one or all of these files can be replaced.
Texture hacking refers to the modification of individual textures in the game's data. Pioneered by the hacker Pharrox, a majority of texture hacks are cosmetic in function, and often take the form of alternate costumes for characters, such as those seen in the images to the left and right. Textures from both characters and stages can be modified, as can various other texture; some hacks, for instance, replace the graphics featured in Peach's Peach Blossom. Particularly extensive texture hacks are also often featured in moveset hacks, such as those seen in Project M and Brawl-.
Music hacks feature the replacement of music tracks and replacing them with tracks that the user prefers to use in the game. Custom music was popularized by GHNeko (one of the main developers of Brawl+), who made a video displaying various stages with custom music, although it was done with a modified ISO. Eventually, Phantom Wings continued his file replacement code used for textures to incorporate music (the first post about it can be seen here). Initially difficult for some users to understand, due to the required use of a .brstm file and necessitating music to loop in an acceptable or desired manner, fellow hacker Bionic Sonic created a tool that required considerably less hacking and editing from the end user's part. The hacker Dantarion later improved on this method.
Music files do not solely represent the songs played on the menu or stages. They also represent the fanfare of a character. The files follow a chronological trend, and in this case, the files are named Y(XX).
In Brawl, leftover music data appears in the form of empty music and fanfare files. For the fanfare files, through the use of cheat codes created by Dantarion, it is possible to give characters their own individual fanfares (though one must also provide one for it to work). In SSB4, the ability to do so returns. The process is much simpler, though as stated above, they will need a file for that fanfare.
Created by Phantom Wings, moveset hacks (known as "Project Smash Attacks" after the identically-named program, as well as "Plan Zeroes" after the first notable moveset hack) alter the movesets of an individual character to varying degrees. This type of hack, however, requires extensive knowledge of scripting and floating values in order to perform, though multiple tutorials exist in an attempt to teach newer users on how to perform such hacks. The first notable moveset hack was "Plan Zero", a moveset hack of Mario. Although not the most popular moveset hack, it became the most widely known amongst hackers after the release of Project Smash Attack. Today, most moveset hacks are more refined than before, and often feature famous characters such as Cloud Strife from Final Fantasy VII, Sora from Kingdom Hearts, Waluigi, and Mewtwo, who was eventually hacked into Project M.
The default models of a character, starting from Brawl, can have their vertices relocated. The model itself becomes reshaped, and in turn resemble the intended design. Texture hacking is done with this to ensure they correlate with the model's new design.
In addition to texture hacking and model vertexing, a character's in-game model can be replaced with another. For this to be done, the model must first be rigged over the character's skeleton. Importing model rips from other video games (like Street Fighter, Marvel vs. Capcom, or even previous Super Smash Bros. titles) are commonplace in Brawl and SSB4, and Melee to a lesser degree.
Some mods like Project M have patched characters by giving them extra costumes. Most are are inspired by other characters (such as Mario in his doctor's attire or Ike wearing Hector's armor); other characters (those of The Legend of Zelda and Star Fox) have costumes that reference their designs in Melee.
This idea, as well as the method below, to add characters allows modders to add a certain character they desire to appear in Smash as playable.
In January of 2014, Phantom Wings created another program called "BrawlEx", an external program that is used to create clone characters. Each one has their own data file when stored on the SD Card or disc, and an independent character selection and portraits in-game. Additionally, one can replace the movesets and models of that cloned character to add characters that are not on Brawl's base roster. This way, one can play as those characters without replacing the original whatsoever.
Ranging from those who appear in past or future installments, were planned to appear but instead became unused content, are overlooked, or even non-existent in Smash all together, the opportunity of adding characters is limitless.
Unusually, all clone engine characters have the same codec conversation as Mario.