The Division: Farming Tips in the Underground from a Level 40 Player

Here's some very helpful tips on how to level up, and get good loot in the Underground based from a level 40 player's experienced. As a proof of my level 40 status, check the images below:

Tip #1: Don't try to level up and loot at the same time

For example: If you are at 228 GS and you want to start doing the Underground, YOU WILL NOT get gear upgrades from operations at all until you reach level 20, and unlock Phase 2 + Heroic difficulty. Well unless you haven't geared up properly for 240 GS sets before this DLC released.

The only sources of "good and reliable" loot to 228 GS players are: Underground Caches and Heroic mode. This is because Caches scale to your GS, and Heroic mode only drops 229/268 GS items.

So here's my recommendation: keep doing Hard mode runs until you reach level 20, THEN you spend some time to grind for 229/268 GS items in Heroic runs. After you've geared up well enough, do Hard mode runs again until you reach 35. By the time you reach 35, you'll have all available directives and phases unlocked, it'll be easy to farm for XP from 35 onwards.

Tip #2: Don't waste Directives early on

Directives are key to faster XP gains in higher levels (like after level 30). For instance, having 3 Phases, 3 Directives at Heroic difficulty gives you ~9200 XP per run. It takes a bit of time to complete, but with a competent group it isn't difficult at all. Also, if you have a bunch of friends to play with, remember to take turns to become leader and pay Intel for Directives. Only the leader's Intel gets depleted in every game.

Tip #3: Try Heroic mode as it isn't as difficult as you think

It is simply a small upgrade from Challenge mode. Lvl 34 ---> Lvl 35, plus higher NPC aggression. You won't even feel it if you're geared properly.

I tried Heroic when I reached 20, back then I was GS 234 with all armor pieces being 240 GS. So don't worry about it. Here's some tips though:

Have one dedicated support to run Tanktician for Smart Cover and Heal.
Have someone run DPS build with BLIND so that he can Pulse as well.
Play patiently. You can't go ham and run around in Heroic, Smart Cover is a pretty decent skill to keep your team unharmed from Shotgunners and Snipers.

Tip #4: Don't kick lower GS players in matchmaking

Because you're probably going to end up being pissed anyways (if the randoms are incompetent). I've been running Heroic at 234 GS with a friend who has 219 GS at the time, and we don't even get wiped out if we do it properly. I've also met countless low GS players who play way better than those who are as high as 252 GS. So if you're going to matchmake, be prepared that there will probably be some skill discrepancy, but that's not due to the GS.

Bonus Tip:

Collecting all Intel (photos and audio logs) doesn't give you the BLIND outfit shown in E3. It gives you the Roadie outfit instead
Reaching level 40 grants you the BLIND outfit
When looting in the locked toilet (you'll know which one), you better go in one at a time. Or else you'll easily get stuck inside loot boxes!
Intel only appears in non-combat zones, usually they're near Ammo Boxes. They always appear at the same spots and it's almost a guarantee that each Phase will have one
Your skills bug out quite frequently in Underground. Kill yourself if this happens, and it should be back to normal
Tactician's Authority frequently gets bugged (the 4 piece bonus I mean) whenever I start a new operation. Remember to check every time the operation starts
You can Interact with the elevator between Phases even if your teammates aren't all INSIDE it. It won't cause any troubles
You can fast travel to your teammates once the Phase ends i.e. after the Boss dies
Duplicate loot means free credits. Remember to sell them!

Tips on Looting

FireCrest and BLIND drop A LOT at any difficulties, just sell them
It seems that all slots of gear sets will drop (be it Kneepads, Mask, Vest etc.)
Older gear sets do drop, but they are very rare e.g. TA, Hunter's Faith, Final Measure
I've noticed that at lower difficulties, Reclaimer/DeadEYE/AlphaBridge drop more often than at Heroic difficulty
Loot boxes at lower difficulties DO HAVE a small chance of giving you 268 GS gear (happened to me ONCE)
I haven't seen a single non 1.3 update weapon from Underground Caches

The glorious B.L.I.N.D outfit

A lot of people asked about this outfit, so here's some screenshots of it:

Cap: