GameMaker Instant Play Decompiler

Games available via Instant Play on the YoYo Games website can now be decompiled following the release of the second version of a GameMaker decompiler authored by Clam.

[Click images to view at full size]

“Anyway, it does pretty much everything the old one didn’t:

  • Decompiles Instant Play games
  • Extracts extensions from GM7 games
  • Extracts Game Icon, exe info
  • Shows a progress dialog rather than freezing
  • Fixes a bug that I know at least one person exploited to make their game “undecompilable”

…I decided to make this tool public mainly because it was leaked, but also to make a point about the gmk encryption. The gmk encryption was designed to stop 3rd party projects, and has effectively achieved nothing but annoyance to these projects. Furthermore, the documenting of the gmk decryption scheme led to its testing on executables and hence the making of this tool”
Clam, GM Decompiler v2.0 publisher

Also on GameMaker Blog:

What do you think?

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  1. I mean it certainly could be used for good and not evil correct? To learn more about gml for instance, or to reclaim a game’s source data which you lost. Point is if they game devs don’t make it open source, that means they don’t want you to see it, and you have absolutely no ethical, or legal right, to view it. If they want to make it viewable by the public, then that’s another story. I don’t want strangers to come inside my house (or my game) so I lock my door and get an alarm system (use a secure exe) and by the logic displayed here, its inevitable that someone, if they want to, will be able to get in anyway so why bother putting the lock, and besides, they should be able to come in anyway its everyone’s rights….. sounds alot more stupid when you try to use it with anything else, because it is stupid logic…. for anything

  2. Why do you even care?
    Everything should be open source anyways. The fact that the gmk files are encrypted is just gay, because you can’t open them in an editor and look at the code, which would make learning to write it a great deal easier.

    Besides, they, like every executable in the known internet universe can be decompiled and reversed engineered, and Mark will never be able to stop that.

    I read something where he threatened to sue the guy who made the GM decompiler.
    This made me laugh extremely hard. Mark, don’t be a douche bag.

    I always give out the src files to everything I ever do, not just in GML. Closed, protected source code is lame, and an illusion. There is no such thing when you get down to it. Everything can be cracked. There are no exceptions.

    Licensing is another joke.

    I should be able to view my src in an editor, then have the option in the compiler to encrypt it at compile time if I wish. Encryption should be left up to the coder, and a good compiler would give the freedom to make that choice, not force it. Anything forced is bad. You trying to play the big brother role like Microsoft and Goodgle? HAHA

    Paying for GameMaker is lame too, or any other software for that matter. It is easily cracked. Thank God for piracy. You need to get with the program and join the open source movement, and screw all this “I think my shit is gold” mentality, LOL

    If you create something and publish it, it is going to get ripped sooner or later by someone, and frankly, there is nothing that can be done about it. It’s not like it’s hard to prove the original work is yours anyways, not if you have a brain.
    Communities like this never cease to amaze me and really have no clue.

    I will do everything I can to promote the decompiling and cracking of GameMaker related things, just because of the mentality I see from people in this community, and you know what? There is nothing none of you can do about it haha.

    Hackers and crackers rule. Thank God for them.

    link removed <— this is a great application. I have already used it 😀
    Next I will be decompiling GameMaker itself on my own and when I do, I will plaster it all over the net.

    • Wow… most of the people here are retards. Sure anything can be hacked with enough effort, but putting security makes it tough to hack, and therefore eliminates up to 75% of the cracking that would be done otherwise. No my games that I made should not be open source for anyone to see and change however they want. It is illegal in most countries including the UK. Open source software is open source because the developers chose to make it so, same reason some game devs in yoyogames give the gmk file instead of the exe. But if I don’t want people getting my code, then I have a right to protect it. Yea if i put a big lock someone can still come along and pick it… but the 500 others who tried to get in before won’t be able to. We know its not 100% effective, but it helps, a great deal. And no, many devs on yoyogames DO sell their games. I’m using this for one and one reason only, to get MY game data back.

  3. “In fact, it’d be easier to sniff out the MySQL password with a packet sniffer instead of decompiling the game.”

    At least n00bs don’t know how, so I feel more save about that.
    But the war will go on against the decompiling for like ever, and I’ll keep supporting the “Against” side.

    ….I don’t know why I’m wasting my time here, my game is ‘safe’ anyway.

  4. Evayr: Putting the MySQL password in the client (and making it interact with the database directly) is pure idiocy in any case. It doesn’t matter if it’s a GM game or not.

    In fact, it’d be easier to sniff out the MySQL password with a packet sniffer instead of decompiling the game.

    The point of using MySQL is that you have to use it server-side. The client connects to your server, which then handles any database connectivity.

    • doesn’t matter how you hack the game. its wrong either way. and as for WHY you hack… well MOST hackers do it for all the wrong reasons, its not like they can just assume you’re doing it for knowledge’s sake.

  5. “Why be afraid of the spread of knowledge?”

    Some games are using MySQL, and are not happy with giving their MySQL info away for free, so everyone can hack it all.
    Also, it’s cowardy to use a decompiler. To make a good game, use your own creativity!

    And I agree with Blijbol; decompiling a game is illegal.

  6. Why be afraid of the spread of knowledge?
    Developers who put their games up on YoYo Games aren’t charging people to play it, so loss of revenue isn’t the issue.

    The only fault I can see with this is people actively stealing hard work, removing the original creator’s name, tacking their name on it, and promoting it as theirs. But those hacks get outed fast.

    Sorry, but I have a open-sourced state of mind.

    • because most of the time… hacking is not the spread of knowledge. I’ve heard the same shit from people who hack consoles and pirate games. It’s not knowledge you’re after.
      And if the person who created the game doesn’t want you to view the source, then you have no legal, or ethical right to view it. They created it and its their choice. Many people put the gmk files on yoyogames. They made their games open source because they chose to, not because you have some god given right to know how they made it.

      and you’re wrong, many game devs on yoyo do charge.

  7. Yeah, that was kinda weird, but I understand what he’s saying… I think.
    He is pretty much saying that if you want to program and want to stay with GameMaker, then Enigma is the next best thing.

  8. asdf I see blue twinkle winkles or something? yay let’s all sing and dance and we can have a party singing songs about songs that were originally about songs until they weren’t

    Maybe one day we’ll grow one and fly, but until then we can fly anyways. If you want scripting, use a real scripting language. If you want security, use a compiled language. Don’t like compiled languages? SHOCK! Enigma is a GM inspired compiled environement thing so let’s all live in the yellow sumarine or something kiss me you’re gorgeous

    • I’m kinda glad this exists, I lost alot of data recently and all i have left now is some exe files from my old games i wanna finally finish.
      but really things like this should be done by YYG. if they offered a service or something to get your data back… but how would you prove it was yours? idk

  9. “I wonder if YYG cares at all…”

    … and you expect them to do what? Release a changed encryption algorithm next week and do it again a week later when someone cracks that one?

    Anything can be decompiled. If a computer can successfully execute it, somebody can take the time to turn those instructions into readable code.

    • that doesn’t mean you don’t try to protect yourself as best you can. That way you limit the damage done. Peoples homes get broken into doesn’t stop them from locking their doors does it?

YYG Wiki still changing…

YYG/GMPedia wiki merge now official