[FILE ENTRY 1] [FILE ENTRY 2] ... [END MARKER] Each file entry:
Key bytes (hex): 0xDE, 0xAD, 0xBE, 0xEF, 0xCA, 0xFE, 0xBA, 0xBE ASCII interpretation: Þ ¾ ï Ê þ º ¾ In some RGSS3 (VX Ace) variants the key is slightly different – but RGSS2A uses the above. Decryption is identical to encryption: applying XOR again with the same key restores the original data. Once decrypted, the data is a concatenation of files stored in a custom container: rgss2a decrypter
while pos < len(decrypted_data): # Read filename length name_len = struct.unpack_from('<I', decrypted_data, pos)[0] pos += 4 if name_len == 0: break # end of archive # Read filename filename = decrypted_data[pos:pos+name_len].decode('utf-8', errors='replace') pos += name_len # Read file size file_size = struct.unpack_from('<I', decrypted_data, pos)[0] pos += 4 # Read file data file_data = decrypted_data[pos:pos+file_size] pos += file_size # Write to disk out_path = os.path.join(output_dir, filename) os.makedirs(os.path.dirname(out_path), exist_ok=True) with open(out_path, 'wb') as out_f: out_f.write(file_data) print(f"Extracted: filename (file_size bytes)") file_count += 1 [FILE ENTRY 1] [FILE ENTRY 2]
def decrypt_data(data, key): """XOR decrypt data with repeating key.""" result = bytearray() for i, byte in enumerate(data): result.append(byte ^ key[i % len(key)]) return result Once decrypted, the data is a concatenation of
| Field | Type | Description | |-------|------|-------------| | filename length | 4 bytes (uint32) | Length of filename | | filename | variable | UTF‑8 string (no null terminator) | | file size | 4 bytes (uint32) | Size of file data | | file data | file size bytes | Raw file content |
def extract_rgss2a(archive_path, output_dir): """Extract all files from a .rgss2a archive.""" with open(archive_path, 'rb') as f: # Read header magic = f.read(4) if magic not in (b'RGSS2', b'RGSS3'): raise ValueError("Not a valid RGSS2/3 archive")