Bypassing DRM, licensing checks, or digital storefront validations built into the game.
The absolute best defense against decompilers is using the for your final commercial release. Because YYC converts your project into native machine code (C++ binary), tools like UndertaleModTool cannot automatically read or reconstruct your scripts. A malicious actor would need advanced assembly debugging skills and tools like IDA Pro or Ghidra to make sense of your code. 2. Use Code Obfuscation
However, with popularity comes curiosity—and sometimes, malicious intent. Enter the concept of the gamemaker studio 2 decompiler
: Most tools can easily extract sprites, music, and backgrounds. However, decompiled code often lacks original variable names and comments, making it difficult to read.
Initially created for modding Undertale (which runs on GameMaker: Studio 1.4), this open-source tool has evolved to support GMS2 and GMS2.3+. A malicious actor would need advanced assembly debugging
The GameMaker VM (Virtual Machine) compiler generates code that runs on a runtime interpreter. This approach prioritizes cross-platform compatibility and ease of deployment at the cost of making the game more susceptible to reverse engineering.
I can provide specific security steps tailored to your build pipeline. Enter the concept of the : Most tools
Over the years, the open-source community has developed sophisticated tools to inspect and modify GameMaker games. 1. UndertaleModTool (UTMT)
The threat of decompilation is real, not theoretical. One GameMaker developer shared their experience: a player decompiled their game's demo to fix a controller bug themselves, then sent the developer screenshots of the fixed code. While this story ended with admiration rather than anger, it illustrates how accessible decompilation has become. The developer noted, "it's as simple as just opening the tool and opening the game exe with it to get all the code".
Because the code is turned into machine language, names of local variables and code structures are stripped away. Reversing a YYC game requires advanced assembly debugging tools (like IDA Pro or Ghidra) rather than a simple drag-and-drop decompiler. The Primary GameMaker Studio 2 Decompiler Tools
Using a GameMaker Studio 2 decompiler raises several implications and ethics concerns: