I'm trying to figure out if it's worth spending 7500 ether for the best C rank drones. As far as I can tell there's no way to get any of the B rank drones without spending real money because either the costs are astronomical (100,000 medals each for Panteron, King Tron and Gunta) or there's no way to get pieces of them at all except for buying chests (Soora, Gato). Does anyone know of a reasonable way to get these guys?