|“||She was sacrificed for she had a cursed fate. Please... I need you to bring back her soul...||”|
–Wander talking about Mono
Mono is quite a beautiful woman with long, dark hair. She wears a long-sleeved lilac dress, but no footwear. Both Wander and Mono were designed with long hair from the start of the design process. Her long, dark-brown hair worked as a contrast to Ico's Yorda, who has short, light-brown hair. At the very beginning of the game, she donned a light-brown cloak that covered her entire body.
With each colossus slain, Mono's voice becomes more audible and clear in the visions that Wander experiences before his return to the Shrine of Worship. At one point, she is seen getting up in a dream after Wander kills the eighth colossus. After Dormin is vanquished (likely only temporarily) and the bridge collapses, Mono finally awakens. Agro, though suffering greatly from an injured leg, leads her to the baby in the now-empty pool at the back of the Shrine. Appearing dazed, yet strangely unsurprised to find herself resurrected from the dead; seemingly unshakable, she picks up the strange baby without so much as a look of surprise. They then head up to the secret garden atop the massive structure.
Mono's Cursed Fate
At the beginning of the game, Wander states that Mono was sacrificed because she had a cursed fate, but does not elaborate on what exactly that fate was. This is one of the many questions that Shadow of the Colossus raises, and leaves to the player to figure out. For the sake of this wiki, we will only look at three proposed "cursed fates", although there are many other possibilities. A combination of these three is also a possibility.
To become the Queen
Some players believe that, due to her resurrection by Dormin, Mono came to gain immortality or some sort of dark power, eventually becoming the powerful Queen. This explanation makes sense because it plays into the tragic nature of Shadow of the Colossus's story, having Wander work so hard to revive her, only to have her turn evil. Some players have also noted similarities in Mono's and the Queen's appearances. It should also be noted that Dormin speaks with two simultaneous voices - male and female -, and when they are fully manifested, the female voice is inaudible. This implies that Mono was brought back to life with the "female" side of Dormin, and would explain why she would become the Queen later. Moreover, Dormin does passively mention at the beginning that it is impossible to return lost souls to bodies -- instead, Mono may have inherited a new one.
To create the lineage of horned children
Others believe that Mono was said to bring the horned children into the world, and so was sacrificed before she could get the chance to. These horned children, such as Ico, are referred to as being cursed or bringing bad luck. The irony in this is that the events that lead Wander to try and resurrect Mono are the same events that lead to Wander's revival as a horned infant, starting the lineage of horned children. If Mono had not been sacrificed in the first place, Wander would not have been compelled to revive her, and there would not be any horned children. The act of trying to avoid the prophecy led to its fulfillment.
To participate in the resurrection of Dormin
Alternatively, it would be logical to assume that the cursed fate was that she was to help in resurrecting the game's forbidden and antagonistic deity. Therefore, we could go as far as saying that Lord Emon would have had her put to death to prevent this, explaining his prayer for her life and soul which we see when Wander returns from killing Malus. This would also fall in line with the aforementioned irony as her death to prevent Dormin's return would have simultaneously instigated it.