Over time, the Resistance grew smarter, more cunning. No longer filled with just brash Gryffindors who dreamt of glory and didn't give a damn about effective battle plans. When their ranks began to swell with former Hufflepuffs and Ravenclaws and even a surprisingly large number of Slytherins, their tactics became much more effective. They began to rely more on guerrilla warfare, on being sneaky and secretive.