Cube
Spend Desire Crystals to draw rewards from the Cube of Rapacity.
The Malice Incarnations will appear when Malice is accumulating in the stage. Kill the Malice Incarnation to collect Desire Crystals.
The Cube of Rapacity will appear upon the defeat of the stage boss. Interact with the Cube of Rapacity and spend Desire Crystals to Covet from it. You can draw one reward from the cube each time you do this, including the Cube of Craving which could make the items from the cube even more precious. After the draw, select and claim rewards to get them. If you have gotten a Cube of Craving during the process, you can also select Greed to have a 50% to double your rewards and a 50% chance to lose everything.