The room contains an Altar of Sacrifice which allows the player to sacrifice an unique item for another random unique item, excluding any drop-restricted uniques. At level 1, the altar will provide a random non-league-specific unique. At level 2, the altar unlocks the ability to provide league-specific drops. At level 3, the altar guarantees a unique of the same type (belt, body armour, etc.) much like an Ancient Orb.
At level 3, the Altar of Sacrifice also allows you to combine an Incursion unique with its respective Vial to create an upgraded version of the item.