After defeating Rennala, Queen of the Full Moon, within the Raya Lucaria Grand Library in , Tarnished adventurers might notice a locked chest sitting near the Queen. Unlike other containers throughout the Lands Between, this chest is locked, preventing you from accessing its contents. There is no key nearby, as the solution does not lie within the world but in a particular NPC's questline in .
The solution to this locked chest lies with the NPC Ranni, the Lunar Princess Demigod who you can encounter as you travel throughout the open world. The first time you meet Ranni, she will be near the Church of Elleh after you obtain your horse Torrent. You may stumble across her randomly during this portion of your travels, but this is the first step to unlocking Rennala's Chest.
A new Elden Ring mod makes the trip through the Lands Between less lonely by letting players summon bosses and NPCs to serve as traveling companions.
The only way to open the chest near Rennala in is by following Ranni's storyline and entering into the Demigod's service. Her main storyline begins once Tarnished has defeated Starscourge Radahn of Caelid, thereby gaining access to the underground Eternal City of Nokron. The stars released from the sky open a massive crater in Limgrave that you can enter once the boss has been taken down.
After speaking with Ranni and her subordinates within Ranni's Rise, the protagonist must retrieve the Fingerslayer Blade from Nokron, hidden within a building in the Night's Sacred Ground. Afterward, Ranni will leave the tower, never to return. Your next step is to use the portal in Renna's Rise to teleport to the northern half of Ainsel River and follow the Demigod's path.
During this time, you can also pursue the questline of Blaidd, one of the best characters in . His story is tied heavily to Ranni's mission but is unnecessary for acquiring the key to the locked chest near Rennala.
Near the Site of Grace in Ainsel River Main, adventurers will reencounter Ranni;
Read more on screenrant.com