Hello everyone,

I’m Mgamerz, owner of ME3Tweaks.com, and the lead developer of the Mass Effect Trilogy editor toolset, ME3Explorer. I also write end user installation tools ME3Tweaks Mod Manager and ALOT Installer. If you’ve modded the series recently as an end user or a developer there is a high likelyhood you’ve used my software to do some or all of it.

Recently, BioWare announced Mass Effect Legendary Edition, which is a remastered version of the original three games. I’d like to share with you what I know about the new games, what they mean for modding, and what my plans are going forward, as I have had many people ask or tell me things that need to be cleared up.


Will existing mods work on Legendary Edition?

No. To be clear, when I say ‘existing mods’, I mean package file based mods, which is the majority of mods. Anything that ends in .pcc, .upk, .u, .sfm are package files, and are what comprise of the majority of each game.

Our files are tied to certain engine versions of BioWare’s fork of Unreal Engine 3. On top of this, each game in the trilogy is on a different build of Unreal Engine 3 with more and more BioWare changes on top, and that spans 5 years of engine development by Epic Games as well. Unless BioWare changes absolutely nothing in their game, things will not work.

Complicating matters is that while our modding tools have improved greatly recently, many mods were built with older, buggier tools, and it is more a bug that they actually work in the game, rather than them actually being properly supported. Many of my older mods even have issues, but the game somehow still works with them.

Essentially, you can think of it this way: Will vanilla package files from the trilogy games work on legendary edition? I’m extremely doubtful, there are too many dependencies on core files that are nearly guaranteed to be changed.


But BioWare says they’re working with the modding community?

BioWare may be working with some people, but I’m not sure who. I’m curious, but I also understand whoever they are, they are under NDA, and asking people things who are under NDA just makes their life more difficult.

However, I’m not under NDA, so I can tell you what I know. Nobody in the toolset development group has been contacted, which consists of three people: Myself (Mgamerz), SirCxyrtyx, and Kinkojiro. We are the ones who build and maintain the tools (ME3Explorer) that are used to make mods, and I personally am the one who also builds the tools that installs the majority of said mods (ME3Tweaks Mod Manager).

These tools are practically required to mod the trilogy (excluding texture-only mods), and all three of the developers know the engine internals in ways that many mod developers don’t – for example, the flags in package headers, various file formats, how property serialization works in our games, Unreal’s memory system, etc.

At this point in development of Legendary Edition, there is not a lot that BioWare can internally change to help with modding. You cannot bolt proper mod support onto a game, it must be done from the start, and nobody reasonable expected BioWare to do such a thing.


What are my concerns?

Ever since Mac Walters tweeted about working with the modding community, I have had dozens of people message me directly about how they’re excited to have existing mods work on legendary edition. Many mod authors are also excited to work on legendary edition.

I do feel that there is an expectation of modding Legendary Edition that is not actually based in reality, and it’s going to cause issues if the game turns out to not be so easy to work with. End users will blame both us, the tool developers, and BioWare, as they feel they were mislead.

They will also blame mod developers because BioWare’s statements made them think this was easy – we have users already come for assistance asking why these games are not easy to mod like Skyrim.


But can BioWare do anything to help?

BioWare for nearly a decade has seemingly taken a ‘do not acknowledge mods’ policy, so for them to say they’re working with the mod community out of the blue is a real whiplash for the scene. I would love to have a conversation with BioWare to discuss things that could help the modding scene that should not take a lot of effort to implement, but I’ll detail some of them below.


1. We need a way to debug the game

ME1 on PC included the application log functionality, which wrote a bunch of useful information to the Documents/BioWare/Mass Effect/Logs folder, including crash information (such as loading an unused mip).

This log functionality was removed in ME2, and all internal debug code also was stripped out, so debugging ME2 is nearly impossible.

ME3 included a blank stub for ‘appErrorF’, which we hooked to get a basic level of debugging, but it’s still pretty weak and often doesn’t have any useful information. Complicating things was the use of TOC files which for years added extra steps to modding that were not required for ME1/ME2.

If you want us to be able to more easily mod the game, we need a way to know what the game engine is doing, or is unhappy about. Can you imagine writing software where the only way you know something is wrong is when the application unexpectedly closes? Because that’s what modding is often like.

We may have advanced tools these days, but when it comes to debugging and fixing a mistake you made, it can be such a frustrating experience that you just give up. If Legendary Edition removes the logs feature and strips out debugging tools we can leverage, it’s going to seriously cripple the ability to mod these games. Even if logging functionality required another edit to enable (such as through the configuration files) it would go a LONG way in helping us.



In the current scene, we load files primarily through the use of the DLC loading mechanism for ME2 and ME3. We recently (about 2 years ago) uncovered some tricks in ME1 to also load DLC overrides in ME1, but it’s weaker and has some caveats, such as not working with movie files and the TLK files being embedded into a billion files (though I doubt this is an issue, as the PS3 version of ME1 did not use this system).

There are some core files that can’t load from DLC, such as SFXGame, which is a real problem because it has a lot of crucial edits. One system that I personally leverage is TESTPATCH in ME3, which can override classes, but we don’t understand how it works well enough to generate new entries.

If the DLC system is removed – which it very well could be, because if this is the ‘best’ version of the games, they won’t need to have post release content, and thus there’s no need for DLC loading – it’s going to greatly complicate modding. Replacing files in the main game is extremely easy to do wrong, leads to wide incompatibility, and is frustrating to support; I know this because for years I wrote multiplayer mods, which required file replacement.

DLC mod loading allowed us to override and remove mods fairly easily. There are plenty of downsides but it is a huge improvement to direct file replacement.


3. Moral support? (optional)

For nearly a decade, modders have built loads of mods – Mass Effect Happy Ending Mod, controller support, bugfix mods, new levels, same gender romances, texture overhauls, etc…

Personally I’ve built about a dozen mods, made many programs, even built an entire web application that can be used to build mods – but I can count on two fingers the amount of times I’ve ever had my work acknowledged by someone at BioWare in any sort of way that actually meant something, beyond essentially them saying ‘cool’.

This is a somewhat weird thing to bring up, but if you look at the creative scene for Mass Effect, there are many areas you look at – artwork, cosplay, streamers, etc, but the modding community is by and large completely ignored, and it is somewhat demoralizing.

We build these mods because we love these games, even if we at times are very critical of your work. This modding scene was actually created because of the critical reception to the end of Mass Effect 3, but it’s because those people loved the series, not because they hated it.

There are likely a lot of legal ramifications that bar you from coming out and endorsing mods, plus a lot of things like ‘is this a reputable person’, etc. that are not really present when you post on a picture on Twitter that someone made. I also know that by tweeting or coming out saying ‘What a nice mod this is!’, people would almost assuredly misinterpret it as you ‘supporting’ mods, rather than just ‘supporting the idea of them’.

That said, it would be nice if the work we do could at least have a way of being acknowledged. For years we have been mostly ignored, and while I’m sure some developers are fine with this, it would greatly improve modding morale if we at least knew someone at BioWare actually cared, or at least thought it was interesting, even off the record. I’m sure there are some people that make these games that do enjoy our work, but you would be hard pressed to find anyone who develops mods that knows that.



Yes, this is a real nitpick, but it’s actually come up when trying to parse files from PS3 and Xbox assets of ME games. If package file headers could have some way to identify their game (something unique, like package tag) it would greatly reduce complexity. It seems small but as someone who works on tools, knowing what game a file belongs to is VERY IMPORTANT.

This is of course assuming that you are unifying the engine versions, which I assume you are, since this was already done for the PS3 versions of the games.


Future plans

I plan on working on legendary edition, but I want to make it clear to end users AND mod developers that things are going to take time. One of the things that greatly concerns me is how news sites are saying how great this game will be to mod based on just a few tweets and an interview that did not really talk about modding.

I want to make sure users and developers understand that modding will take time, will not work on day one, and likely will not work on month one, and will likely have serious teething issues possibly for years.

As someone who works at the top of the modding chain, a lot of the development efforts have fallen to me – a developer needs a feature in Mod Manager for their mod? I have to implement it. Need an easier way to edit game files? One of the toolset developers typically has to do it – and we do this for free on our own time.

The other developers I work with (SirCxyrtyx and Kinkojiro) are great people who have all done years of research and development, and together we’ve built lots of great tools and features, such as Pathfinding Editor, entry porting and relinking, dialogue editing tools, and more.

I personally spent YEARS developing and refining Mod Manager and have spent years completely reworking ME3Explorer into a much more professional grade tool. Our scene is much healthier than it was back in 2013-2015 when our tools were still immature, making and using mods is far easier these days. Some of this progress is going to be reset with the release of Legendary Edition.



Short answer, no. We will have to wait and see. I do not have any plans to have ME3Tweaks Mod Manager work on LE – it will require me to build a new tool, as M3 is very tailored to the current games, tools and codebase. ALOT Installer will not be necessary (hopefully!), and ME3Explorer may be forked into a new project depending on how much has changed internally, but we don’t really know anything useful yet. 

Personally, I am not a fan of trying to build a conversion tool between the trilogy games and legendary edition, as it would be a monumental amount of work, especially if we don’t understand changes to the internals of the games (including many things we currently don’t know about the existing games). The toolset already supports about 7 or 8 games across 4 different platforms, adding another 3 will be significantly complicate the codebase. But it really depends on how much is changed.


Anything else?

Yeah, the last thing I’d like to mention, is that a lot of this post is about the developer side of things. Myself, SirCxyrtyx, and Kinkojiro have all done absolutely masochistic things in the name of research and development (but especially Kinkojiro), but the flip side is that there are far more users who have little to no patience even installing mods.

If installing mods is difficult (such as a complicated system without a DLC loader), many users will not even attempt it, and this leads to diminished returns on the development side. I work on both sides of the coin, writing the tools for installing mods, as well as developing them, and over time  I’ve adjusted my software to make it easier for users.

I’ve noticed that as it becomes easier to install mods, more developers have appeared, and part of it may have to do with decreased support time for mods. My end-user tools for example have a very detailed diagnostic system that can be used to identify a wide variety of issues, which means users don’t have to ask developers how to fix things.



I believe our modding tools for legendary edition could be greatly improved if we had someone we (the modding toolset developers) could talk to at BioWare about, as there are still many gaps in our knowledge of BioWare’s proprietary changes to the engine that significantly hinder our efforts. With the release of Legendary Edition, those knowledge gaps will likely significantly widen. 

Want to have a talk about some other things the scene could use BioWare? Drop me a line at femshep AT me3tweaks.com, there are many small things that would greatly reduce the friction of modding that would really help set up the scene for success.

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