Cornerstone is one of the quests on offer from Saint-14 now that he's returned to Destiny 2. Players can pick up his errands from him in the Tower Hangar. Here's how to complete Cornerstone.
Cornerstone Destiny 2: How to Unlock the Tower Obelisk
The first step of the Cornerstone quest line is called Some Assembly Required. This tasks you with collecting 10 Crucial Fallen Components, 10 Crucial Cabal Components and 10 Crucial Vex Components. You'll have to hunt down enemies with orange bars or higher to find these components.
Once you've collected all those pieces, return to Saint-14. He'll give you an obelisk you can place in The Tower. Go to the spawn location and place the obelisk to activate it. This will give you access to the Tower obelisk, which will let you manage other active obelisks.
We recommend you complete this quest alongside the Tribute to the Colonies quest, as they can be fulfilled at the same time with relative ease.
