After depositing a sufficient number of runestones, the Sin Eater will change location, marked by the star icon on the mini-map and your HUD.
In Harvest, you’ll collect runestones from fallen zombies and deposit them into the Sin Eater obelisk. The initial objectives are as follows: Harvest, Transmit, and Blitz. At first, you’re presented with three different portals, each offering its own objective type.