Avoid the Knight Spirits that'll appear, because they're traps that could cause them to Elden Ring Runes push Tarnished away from the bridge.
Walk around the first tower, and then cross the second bridge.
Turn left and then use the lift for access to the top level.
Then, light up the Site of Lost Grace, then exit the room. There are some Direwolves in the area Be cautious. Follow the large staircases that lead past the Giant Troll along with the Pages until a massive archway in the middle is visible. Inside it is Royal Knight Loretta and the door into the Three Sisters. Beat her out and then sprint to the door using Torrent. Three massive towers can be seen from afar including: Renna's Rise, Ranni's Rise the Seluvis's Rise.
To encounter the spectral form Go to the tower in the middle and climb to the top floor. Contact Ranni to begin her quest. After that, head back to cheap Elden Ring Runes the ground and speak with Seluvis. Seluvis will inform players that in the event they need his help, Tarnished is located inside his tower.