WARNING: THIS IS A THEORY. THIS CAN ALL BE PROVEN INCORRECT, JUST AN IDEA I HAD DURING ONE OF MY SLEEP-DEPRIVED MARATHONS. The Fallen you meet in Destiny 2 aren't really that similar to the good old space pirates we have today. For starters, their behavior is completely different than the other Fallen houses we've fought before. The new Vandals crawl around at times, more like a wild animal than a regular Vandal we've fought before. Along with this, there's a whole new enemy melee type named the Wretch. The Wretch carries a crudely made spear and seems to charge you in combat with no regard to its own life. When attacked by Vandals carrying swords in the past, there's a sense of elegance when they swipe at you. This is not the case when attacked by these Wretches. The Fallen in Destiny 2 also seem to be lower tech in terms of gear than other Fallen houses. The spears and blades these Fallen carry seem crudely made out of mixed metals. Why is that? I believe it has to do with where they are. Nessus. A vex planetoid that just reentered our system cause of its abnormal orbit. Is it the orbit? The planet is now a big vex machine at this point. What are the vex capable of? [i]Time travel.[/i] What my theory is, is that this Fallen house isn't newly made. It's older than the Last City itself. This may be one of the fallen houses thought to be destroyed during the whirlwind when actually, they were lost in time. It then makes sense why the technology is so different compared to the rest of the Fallen we face. The Fallen we fought before had [b]centuries[/b] to scavenge parts and resources to build themselves up. But to these Fallen, they've just begun to chase after the traveller, with low supplies, and have only begun to rely on ether to survive began to turn feral, or savage in a sense. They begin creating makeshift weaponry, and forge armor out of scraps to survive in this harsh machine world. That's when we return to Nessus. What may have been centuries to us may have only been days, or weeks to them. With the hints that Uldren Sov has become the Kell of Kells, this is a smart way to keep the Fallen as an enemy faction, as they have no clue all the fallen have been reunited under one banner with humanity. (This relies on Uldren siding with us or if he even [b]became[/b] Kell of Kells) TL;DR: The Fallen on Nessus may be from the past as Nessus may have the ability to time travel as it is a vex machine.