A lot of game tweaks are possible for the PC version of Mass Effect 3, both in terms of graphics and "cheats", and can be done by editing Coalesced.bin. Most of the results you find when you Google for how to do a tweak or cheat will tell you which ini file and variable to change, but not exactly HOW to do that.
Warning before you start: I do not recommend using any "cheats" or a modified Coalesced.bin file if you are going to play multiplayer. You may end up banned. See here.
The coalesced.bin file is basically a collection of variables that the game uses to determine different things, from graphical effects to key bindings to things like shield recharge rates. You can affect the game in fairly signficant ways by modifying this file. To do so, you'll want to grab the ME3 Coalesced Utility.
ME3 Coalesced Utility? What?
It's a tool that unpacks the .bin file so that you can edit it, and then repacks it when you save. There are many ways you can do this, but this is the easiest to use tool that I've found. You can grab it here.
So where is coalesced.bin?
- Its in your Mass Effect 3 install directory, under \BIOGame\CookedPCConsole.
Err... okay. Where's my Mass Effect 3 install directory?
Okay, I've got those. Now what?
- Make a backup (i.e., copy and paste somewhere) of your Coalesced.bin file first. You'll want this as a backup in case something goes wrong, and also so you can swap back to it if you're going to play multiplayer.
- Run the tool. Go to File->Open.
- Select the Coalesced.bin file discussed above.
You should get a screen that looks like this:
Okay, I'm ready! What settings can I tweak?
Way more than I'm going to go into. If you want to know if something specific is possible, either Google for it or post a question and ask.
One common usage will probably be to bind keys to commands so that you can manually trigger them in-game. For example, this is how the current answer about how to tweak your Field of View does it. You smack a numpad key and it changes your FOV. In general, you can do a lot of things this way by doing the following:
- Go to bioinput.ini->sfxgame->sfxgamemodebase->bindings
- (see screenshot below) On the right hand side, scroll to the bottom and enter something that looks something like this: (Name = "NumPadZero", Command = "something")
- Obviously, you could use NumPadOne, NumPadTwo, or whatever you like.
- Replace "something" with the actual command you wish to execute.
Here are a few example commands:
- fov 90 - As already mentioned, you could set the FOV to 90 (or any other number) this way
- initcredits 9999999 - will set your credits to 9999999
- initammo 999 - give yourself a bunch of ammo
- God - turn on god mode (though instant-kill attacks can still kill you)
This page lists even more commands.
Again, this is about how to edit the file, not necessarily what to edit. If there's something you want, like how to unlock all weapons (which you can do), Google it and and you'll probably quickly find the command you need. Or ask a specific question about what you want to do (via the "Ask a Question" button up top, not by leaving a comment on this answer). I'm not trying to turn this answer into a repository for every possible cheat and tweak. The purpose was to explain to you how you get to the point where you enter these commands in the first place.
Can I use this with multiplayer?
I do not recommend you use this with multiplayer! Yes, I said this already. It was worth saying twice. I have seen rumors that EA might block/ban players who are using a tweaked file, since they could use it to cheat. I'm trying to get a definite answer on if non-cheating tweaks will be a problem, but for now, better safe than sorry.