Tom Clancy's The Division

Update 1.4 for the game greatly changed the balance and the amount of experience that goes into gaining levels. Therefore, getting a 40 underground rating is now not such a stupid, long and stupid trophy in this game, although it will still require you to waste a lot of time. It doesn’t matter what or how you do it, it will still take you a decent amount of hours of stupid grinding to get it. The only full-fledged way to gain underground “experience” is to perform operations. No, you can still get a limited amount of experience for collecting audio diaries and digger recordings, 200 experience for each: a total of 16,000 in total, which is a drop in the ocean. For collecting records, see the hint for the “Gone Spelunking” trophy.

Therefore, he will consider the option of effectively gaining experience for completing operations. First of all, please note that experience is always awarded only after the successful completion of the operation - if you complete stages 1 and 2, and then die as a whole team in stage 3, you will receive 0 experience. Killing enemies and using various bonuses for increased experience do not speed up the arrival of underground experience.

For each level of the underground rating from 1 to 39 you will receive a closed chest. The chest will contain one random item, weapon or clothing from the set. The item level depends on the overall level of your equipment. For moving from level 39 to 40 you will receive a set of clothes “S.V.E.T.” (BLIND).

You can get the most experience for a three-stage heroic operation with five directives, at the fifth level of the mine. However, undergoing such an operation for the sake of experience is pain and masochism, plus the time costs will not pay for themselves. Since you will spend a huge amount of time on each stage, and even miming the monsters that are not necessary for cutting out will not significantly reduce the time spent, on average you will still end up with half an hour of pain and suffering per stage.

Now the fastest and easiest way is to go through three stage operations at a difficult (second) level without directives. For this you will receive 4400 experience, in time you can do it in half an hour. If your team is of a high enough level and you are well dressed, you can switch to the challenge difficulty level or add directives, this will speed up the process of gaining experience, but the main thing is not to overdo it, so as not to slow down the passage of time.

To create such an operation, the leader must be level 35, the level of other players does not matter (you can safely finish off the Pugami group through matchmaking, although it does not work now). However, this is not necessary; unlike many other activities, tasks are adjusted to the number of players in the group. Also, always ignore all enemies in places where the conditions are “explore” or “find” until you get to the end point where there is a clear task or a timer appears, this will significantly speed up the passage. (Important: The amount of average experience gained for each stage in operations of 2 stages and 3 stages is the same. So, having reached level 30, you will reach the level of experience that can be obtained in one stage. The only bonus of a three-stage operation is that you save about a minute on loading screens. Thus, the overall efficiency is slightly higher).

After the release of patch 1.4 dated 10.25.16, the tunnels were fixed in the direction of fast pumping, very fast.
You can now go to one in 1 world , in 3 stages with 4 directives
or with partners in the 4th world, but as practice has shown, random people waste time and spoil the nervous system of both themselves and those around them.
The level varies from 15 to 30 minutes depending on the tasks.