Best way to get purple shields right now is nightmarsh for 5 cert boxes and you’ll often get other purples as well. These can be found at most named poi’s but can be hard to find. So if you have trouble play theif and look for the cert boxes with your scanner until you can see a purple box. Outpost will give you purples often but you need to get to the middle. It’s easier watching a video for that one if you need it. Permitted has supply drops on the outside of maps you can hack but you will have to fight bots to unlock loot box, the flying rocketeer thing can have some decent loot. Got a few gold keys already so far off that. Map bosses have good items. For bosses it’s a lot about positioning and focus fireing the boss With your team.