The tool you’re referring to—"RPG Maker XP/VX/VX Ace Decrypter" by Falo—is a notable piece of software in the RPG Maker reverse-engineering scene. Here’s a breakdown of what it is, why it’s interesting, and the context around it.
The "RGSS" stands for Ruby Game Scripting System. The a at the end signifies an archive. The decryption key is hardcoded into the engine itself, making it effectively a "locked box" rather than a cryptographic fortress.
The RPG Maker Decrypter by Falo supports the following versions:
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