metadata, game_state = extract_save("1-1.save") store = game_state.get("store", {}) store["money"] = 9999 store["inventory"]["health_potions"] = 99
import gzip, pickle, json def extract_save(path): with gzip.open(path, 'rb') as f: magic = f.read(4) # b'RPySD' meta_len = int.from_bytes(f.read(4), 'little') metadata = json.loads(f.read(meta_len).decode()) data = pickle.load(f) return metadata, data
init python: def modify_save_data(data): data["player_hp"] = 100 return data config.save_json_callbacks.append(modify_save_data) renpy edit save file
def repack_save(metadata, data, output_path): import io buffer = io.BytesIO() with gzip.GzipFile(fileobj=buffer, mode='wb') as gz: gz.write(b'RPySD') meta_json = json.dumps(metadata).encode() gz.write(len(meta_json).to_bytes(4, 'little')) gz.write(meta_json) pickle.dump(data, gz, protocol=pickle.HIGHEST_PROTOCOL) with open(output_path, 'wb') as f: f.write(buffer.getvalue()) Ren'Py uses custom pickling for displayables, transforms, and screens. Corrupting these objects crashes the game on load. 3.3 Save File Decoder Utility (Python) Below is a safe read-only decoder that outputs human-readable state:
import pickle with open("persistent", "rb") as f: persistent_data = pickle.load(f) print(persistent_data.__dict__) # Persistent object attributes – use same pickle.dump after changes. Caution: Many games checksum persistent data or store encrypted achievements. Editing may lock achievements permanently. 5. Risks and Consequences | Risk | Impact | Likelihood | |------|--------|------------| | Save corruption (unloadable) | High | Medium (if editing by hand) | | Broken script flow (e.g., flags mismatch) | Medium | High (if editing complex games) | | Anticheat detection (online/leaderboard games) | Account ban | Low (most Ren'Py games are single-player) | | Inconsistent state (e.g., item without flag) | Game softlock | Medium | | Checksum / hash mismatch (custom protection) | Save rejected | Game-specific | 6. Alternative: Using Ren'Py's FileSave / FileLoad Actions For mod developers: Ren'Py allows custom save/load handling via Python: metadata, game_state = extract_save("1-1
#!/usr/bin/env python3 import gzip, pickle, json, sys def decode_save(filepath): try: with gzip.open(filepath, 'rb') as f: magic = f.read(4) if magic != b'RPySD': print("Not a valid Ren'Py save file") return meta_len = int.from_bytes(f.read(4), 'little') metadata = json.loads(f.read(meta_len).decode()) print("=== METADATA ===") print(json.dumps(metadata, indent=2))
For most users seeking to alter game variables (money, stats, unlocks), enabling the developer console and using Shift+O is the recommended approach. Caution: Many games checksum persistent data or store
data = pickle.load(f) print("\n=== GAME VARIABLES ===") store = data.get('store', {}) for k, v in store.items(): if not k.startswith('_'): print(f"k: repr(v)[:100]") except Exception as e: print(f"Error: e") if == " main ": decode_save(sys.argv[1]) 4. Editing Persistent Data The persistent file is a single pickled object (not gzip-compressed in older Ren'Py, but may be in v8+).