After you're done with Destiny 2's Forsaken campaign, there'll be a lot more to do, especially if you get the expansion packs that follow. However, one of the tasks available after beating Forsaken itself is the opportunity to present an Offering to the Oracle near the Divalian mists, and you're going to want to complete it if you want to remove the curse from your Reverie armor.
Where To Get The Offering
So, when you've cleared Forsaken, you will get access to the Dreaming City, a location replete with secrets and new things to discover. The Oracle is one such secret and presenting an offering will get you a new quest called Purification Ritual and some fresh gear. Completing that will grant you the Transcendent Blessing, which removes the Riven's Curse from all Reverie Armor. Not having an offering will see you told off with a "You lack an Offering" message.
To start things up, pay Petra Venj a visit in the Dreaming City and buy the Gateway Between Worlds weekly bounty. You'll receive the offering after completing said bounty and you'll need to get it to the Oracle thereafter.
The Gateway Between Worlds costs 40 Dark Fragments, so it would be in your best interest to take a bit of time to form them. You will be prompted to get through the three tiers in the Blind Well, which could even get you another Seed of Light. The Blind Well, referred to as an evolved Court of Oryx, sends waves of enemies upon activation and is similar to Escalation Protocol in that sense. It ends after you kill an Ogre.
Once you're past the Blind Well and its boss, find the bounty in your pursuits and unlock your Offering to the Oracle. All you have to do next is find the Oracle and then present it.
Finding The Oracle And Presenting The Offering
You can do this by starting at the Divalian Mists and darting straight ahead. Go through the riverbed and keep a sharp lookout for a tunnel covered in blue crystal on the left side. Go in there and you'll eventually come upon the temple you saw after beating Forsaken. Once inside, look up to find the giant spinning Oracle and use the stairs or jump up the platforms to get to the tablet. Follow the prompt to present the offering and open the chest that appears on the ledge next to the tablet to collect your rewards, as well as the Purification Ritual quest.
The quest's requirement is a bit random and, while you might be tasked with killing Knights during the Ascendant Challenge, other players might be asked to go through The Corrupted strike. Fulfill whatever the quest requires you to and deliver the bounty to get the rewards, which includes the Transcendent Blessing.
The Blessing is quite important, as it removes the curse from the Reverie armor but keeps the benefit of dealing more damage in the Dreaming City. In short, you'll be able to wreak more havoc over there but you won't suffer additional damage like you would prior to obtaining the reward.
While this is quite a bit to do, the Offering for the Oracle is crucial for players who want to deal extra damage while in the Dreaming City.
Of course, a lot more has happened in Destiny 2 since this quest was a main sell, but new players should try to do as much as they can in the lead up to Shadowkeep. It's quite natural for gamers to want to start from scratch when a new game or expansion drops - if they've never played a game from the franchise before - and a guide is always helpful.