Exploring Balthazar's private quarters in Moonrise Towers during Act 2 of Baldur's Gate 3 presents players with several intriguing secrets and environmental puzzles. Among these mysteries, finding out what to insert in ancient altar in BG3 allows adventurers to unlock a hidden chamber filled with valuable loot and unique story interactions. Knowing exactly how to trigger the mechanism and what items are required ensures that you do not miss out on powerful rewards.
Locating the Hidden Altar in Moonrise Towers
Before you can interact with the altar, you must first reveal it behind the secret bookshelf in Balthazar's room. Interacting with the incorrect protruding books triggers dangerous traps, so picking the proper book on the bottom left is crucial. Once activated correctly, the bookshelf shifts aside to expose the ancient stone altar.
Choosing the Correct Item for the Altar
To operate the altar mechanism, players need to place a fresh human heart onto the pedestal interface. Suitable hearts can easily be gathered from the corpses or bloodied tables located throughout Balthazar's quarters. Alternatively, placing Karlach's head into the slot will also activate the device if you happen to carry it.
Unlocking the Secret Chamber Rewards
Inserting the correct sacrifice opens a secret passageway into a hidden laboratory containing rare items. Inside the room, adventurers can collect the Coldbrim Hat along with useful alchemy potions from a heavy chest. The area also houses valuable lore notes detailing the true nature of the Nightsong.
Interacting with the Ritual Circle
The secret room also contains a damaged ritual circle accompanied by broken Moonlanterns. Bringing Gale into the room unlocks special choices regarding whether to craft a unique Shadow Lantern or destroy the circle. Destroying the circle grants a permanent Advantage on concentration checks, while repairing it provides a shadow summoning item.
