Complex sentence: The most interesting part is that these robots, called Overkill Engines (OKEs), cannot be directly controlled in battle; you must program them beforehand to behave in a certain way under certain conditions using a flow diagram system.
Split into simpler sentences: The most interesting part is that these robots, called Overkill Engines (OKEs), cannot be directly controlled in battle. You must program them beforehand to behave in a certain way under certain conditions using a flow diagram system.