so i'm reading Looking for Alaska and just came to Alaska's line 'Sometimes you lose a battle. But mischief always wins the war.'
maybe it's just how much Harry Potter has been on my mind recently, but these words hold very true in his story...
the most obvious ways are with the Marauders. as part of the first Order, they all took untold steps against the Death Eaters. James is mentioned in the prophecy to have defied the Dark Lord three times. and again, in the books we see Sirius and Lupin save the day multiple times.
in addition, their Map was essential more than once, particularly in discovering worm Tale, who it's true, betrayed everyone, but in doing so, he helps fulfill the prophecy and victory. first, he gives up the Potter's location in Godric's Hollow, leading Riddle to attack Harry and create their connection. then when he returns to Riddle he brings him back out of hiding, and performs the right that gives him a new body, which can actually die this time. and his final act of betrayal is actually show Harry mercy...don't get me wrong, he's still the Marauders' Judas Iscariot, but that goes both for his betrayal and it serving the greater good...in a way.
returning to James, let's face it he and Harry put the cloak to as much use while 'up to no good' as in heroism. it is the cloak though, that ultimately allows Harry to confront Riddle in the forest, disappear into the resumed battle, saving lives along the way and confront Riddle for the final time.