Destiny 2

How to unlock the nightfall strike: The first thing that you must complete is the main story line in Destiny 2. This will allow you to meet up with Zavala and the rest of the vanguard at the and accept a brand new milestone. The first part of the milestone is completing two normal strikes. After that, return to the tower and talk to Zavala who will then grant you access to the nightfall strikes. Easy peasy, now here comes the challenge.

Completing the nightfall strike: The nightfall strikes in Destiny 2 have changed quite a bit compared to how they used to be in the first game. The first major change is that there is no longer any specific burn (solar, void, or arc) for the strike. This is because the burns are changed about every minute or so. This means that you may start off the strike with solar weapons doing more damage, but a minute later, the burn will switch to arc and arc weapons will do more damage. You will get a notification at the bottom left hand corner of your screen whenever the burns switch.
The nightfall strike also has 2 new modifiers called "Time warp" and "Prism." The first modifier now makes the strike timed. As soon as you spawn in, you are given 11 minutest to complete the strike. The nice part about this however is that for every small enemy, such as a vandal, will net you an extra 2 seconds to the clock and every large enemy, such as a yellow bar enemy, will reward you with 7 extra seconds on the clock. The second modifier basically makes it to where attacks matching the focused element deal increased damage while all other elemental damage is reduced. That means that if you are trying to shot a void weapon at an enemy while the active burn is solar, your damage will be reduced.

The time aspect of the strike makes this a very difficult and fun challenge. That is why you want to make sure you and who ever else is joining you is caring the right load-out and well leveled. The recommend light level for the strike is 240+. Don't think that once you hit 240, the strike will be easy. Myself and two friends were around the 260-270 mark and we still had a few bumps. Now with the load-outs, you want to make sure that your fireteam has at least one of each burn, especially with power weapons. For example, I had a arc power weapon while my 1st buddy had a void heavy and my 2nd buddy had a solar heavy. Do the same with your energy (secondary) weapons as well so that everybody is able to do adequate damage. When you get to the point where you don't have any weapon that does the required burn, but your other two mates do, let them do their thing and you just shoot with your kinetic weapon as unmatched burns will do decreased damage.

Communicating is key as you want to make sure you call out whenever the burn changes or when you may need help. If you die, you have 7 seconds before you can get revived or you can simply wait until the timer runs out and you can revive yourself. That is perhaps one of the other bigger changes. If everybody in your fireteam goes down, you don't get sent back to orbit and sent back to a previous checkpoint. You must simply wait until you can respawn, but this of course is a huge time waster for the long run, so try not to let this happen.

When you get to the end of the strike, communicate to where you can use all three of the teams supers on the boss at once as this can do very good damage to whoever is the weekly boss. Through my own experience, my fireteam and I all switched to a arc super and waited for the burn to change to arc, which is when we used our supers.

The nightfall strike will change each week in regards to the strike, but I don't know about the modifiers (I will update guide if there is a change on that). Other than that, I believe that is all the info you guys could need or find helpful when it comes to finishing a nightfall. I hope I gave an in depth view and if you have a suggestion, let me know and don't just downvote. Cheers

Edit: For the week of 9/12/17 through 9/18/17 there is one addition to the Timewarp modifier, in which there are rings placed throughout the strike in which jumping through them will add extra time to the clock. This modifier is called "Timewarp-Rings." It seems to me that for each new strike that the nightfall will feature, this modifier will be changed around in some way to match the specific strike.

Edit: For the week of 9/19/17 through 9/25/17 there is once again a new addition to the Timewarp modifier, in which there are glowing objects placed throughout the strike which by shooting them, you will net an extra 30 seconds for each one shot. Along with Prism, there is a brand new modifier added this week called attrition, which limits natural shield and health regeneration. In addition to totally changing the game on this week's strike, there are no burns, so just use your best weapons and make sure you hit all the anomalies for the +30 seconds.

Edit: For the week of 9/27/17 through 10/2/17 the Timewarp modifier has a new addition, in which there is no way of increasing the strike timer. You are given a certain amount of time and you must finish it in that time. In addition to this week we also have the Torrent modifier, which greatly increases grenade, melee, class abilities, and super.