"We won, we can rebuild, and you can all live your lives and it will be... perfect... it will be fine. (...) And we can grow from this! We can become something so much more! We lived! We survived!" ~ Siduri
Siduri's true nature was unknown to her peers, causing distrust by some and speculation by many. As she was the persona of her helmet, she never took it off and never ate, drank, or slept.
She was a close advisor to King Luistrog and earned the jealousy of his court sorcerer who speculated in his journal that she was some manner of demon or celestial. Despite his misgivings about her, the sorcerer did note that she made no demands for prayers or sacrifice or anything else in exchange for acting as the king's adviser. He also noted that she was very wise, proficient in combat, knowledgeable on a great number of subjects, and able to read dead languages with ease. This is because some select information is retained through the Helm's many lives while most is involuntarily discarded.
She led the remnants of the kingdom in their last battle against the forces of Gnash and was victorious, though King Luistrog perished in the battle. In their moment of bittersweet victory, Siduri and the other survivors were attacked by Stillhavity's toy, Raunfalt, and slaughtered. When Raunfalt killed Siduri, the Helm fell off and the insides of its host body spilled out as black ichor.
The party has only met Siduri through Lusitrog's memory of that life. They initially learned of her existence through Visions they saw when raising flags at Hellmouth's Grave and from reading fragments of a journal written by King Luistrog's court wizard. Though Luistrog and Siduri are the mind of the Helmet that they share, they are considered by Luistrog to be different people.
Luistrog remembers his previous life as Siduri, but considers himself to be different from her. He chose the name Luistrog in honor of Siduri's fallen king. He laments that one day, the memories of Siduri will fade as he moves from his current life to the next in his ever-lasting cycle of rebirth and amnesia.
- The sorcerer's tattered journal noted she "says she's a cano____" where the last part was illegible and he also notes that "she is them" meaning she is a collection of something. However, it;s possible his speculation was incorrect and that these ponderings are not reflective of the Helm of 1,000 Hearts' true nature.
- The sorcerer's ghost says Siduri is an "ancient creature", refers to her in the plural and as "two parts of one whole." He correctly guessed that Siduri was the helmet, but may not have before his death.
- Nicknamed "Jane Dark Souls" by Panic in a reference to Luistrog's similar nickname.