Silent Line doesn't do anything drastic to AC3's formula but instead delivers an absolute smorgasbord of new parts to a genuinely insane degree. EVERY mission has hidden parts to collect, hell, some levels have up to 4 or 5 parts to obtain. There are also part rewards for completing a certain amount of missions with each leg type, the typical part rewards you gain from company loyalty points or arena match completions. In addition, you have every part from the base game return (albeit at a limited selection until you complete a handful of missions) providing over 400 parts altogether. It certainly lives up to its reputation as an expansion, as there's an absolute wealth of options to play with here that SL makes AC3 look fairly basic in comparison.