For those of you that haven't played Diablo 3, one of the end game activities in it are these things called Nephalem Rifts. Basically, these were randomly generated dungeons that had randomly generated mobs for you to kill. You also had a progress bar that filled up as you killed enemies and the goal was to get it to 100%. You progressed through the different levels of the dungeon killing enemies. Once the bar was at 100%, a boss called the Rift Guardian would spawn. Again, this boss was random. Once you killed it, you would get a ton of loot and you could finish the rift. If there were more levels to rift, you could go deeper for more loot, but no other bosses would spawn. Eventually you would find the end of the rift. Then you could finish the rift by talking to an NPC and then rinse and repeat. When you killed the Rift Guardian, it would drop a Greater Rift Key which allowed you to do Greater Rifts. They are basically harder versions of Rifts that are also timed, but you could potentially get more powerful loot. These were also leveled so the higher level the Greater Rift, the harder it would be and the more loot you could get. Like doing a level 90 Greater Rift is pretty damn hard, but you would get a shit ton of legendary gear from the Rift Guardian. I feel like Bungie could have done something similar in Curse of Osiris. It would make sense because the Infinite Forest simulates so many different realities. The Rifts in Diablo are basically simulations. I could easily see something like a rift in the Infinite Forest where it simulates a random planet with random enemies. That would have been really cool and it fits the theme of the DLC.