I'm legit...no need to farm. There's too much to do, I gotta max my vanguard marks, I gotta max my crucible marks, I gotta do the bounties, I gotta do the Daily Story mission, I gotta do the Daily Crucible match, I gotta do the weekly heroic and attempt the weekly nightfall, I gotta collect the materials needed for upgrades... ....And much more. How do you even find the time stand in front of a cave and kill weak AI for hours? It's pointless... I have 3 exotics, 3 legendary weapons, 3 Legendary pieces of armor, and never did I ever farm these minions. Do yourself a favor, and stop collecting green engrams in front of caves.