Warning: Contains some end-game spoilers for Horizon Zero Dawn
Horizon Zero Dawn is full of mythological references, from the names of the central AI components of Project Zero Dawn (Greek myth), to the original names of many of the machines created by Faro Automated Solutions (Egyptian myth). Many of the references are subtle enough to be a nice nod for players to recognize and they add an extra layer of depth to the game’s lore.
While some mythology is a little more overt within the world building, other influences are merely hinted at through the use of mythological archetypes. The High Matriarchs of the Nora tribe are indicative to the mythological archetype of the triple deity. In Greek mythology, the triple deity or goddess is generally represented by Hecate, Persephone, and Selene although it can be argued that the Fates (also known as the Moirai) and the Furies could be considered a type of triple goddess in their own way, even though the prior group is labeled as such more often. There are other incarnations and combinations of the triple goddess within Greek myth, but these are generally the most recognizable. Outside the Greek triple goddess, there are also the Norse Norns, which can be interpreted as similar to the Fates in that they represent the past, present, and future (literally “become”, “becoming, “is to be”–just think of Galadriel’s Mirror) and help to forge the destinies of various beings(source).
In the case of Horizon Zero Dawn, the High Matriarchs can be loosely interpreted as representative of the Norns and a generalized triple goddess figure. While the player mostly interacts with Teersa and Lansra, the other high matriarch Jezza does make her opinion of player/Aloy apparent when she choses to help anoint Aloy as a Seeker despite Lansra’s clear opposition. Within the Nora tribe, the High Matriarchs act as the moral and spiritual leaders of the tribe while the War Chief (who can be male or female) handles the protection. Ultimately, it is the High Matriarchs who hold the final say when it comes to most matters within the tribe. While the game does indicate that there can and likely are other Matriarchs and High Matriarchs, the player only sees and interacts with the three aforementioned women. Teersa acts as a guide and supporter of Aloy while Lansra is an antagonist who opposes Aloy and her exploits. Jezza seems acts as the middle ground between the two, although due to her lack of dialogue it is difficult to make a distinct opinion on this. It may be that Jezza is a newer High Matriarch and thus, isn’t able to voice her opinion to the same degree of the other two.
The actions and roles of each of them set up the potential for them representing the past, present, and future of the tribe–helping to shape the tribe’s future like the Norns. Lansra holds to old traditions and fears that Aloy is a ploy of the metal demons or an omen of destruction. She represents the past, traditions, and the fear of change. While Teersa still clearly follows and believes in many of the old stories and traditions of the Nora she is still willing to see change so long as it follows the will of the All-Mother. She sees Aloy as a sign of hope for a new future and thus, she is representative of the future. Jezza is mostly silent and appears to judge events as they unfold, torn between the knowledge of the past that Lansra offers and Teersa’s willingness to accept change and create new traditions. Jezza represents the present or middle ground. While traditionally the Norns or Fates are represented through women at different points in their lives (Maiden, Mother, and Crone if we’re still using archetypes), due to the way that the High Matriarchs are given their authority, that aspect of the archetype was likely left out, but the other remnants of it can still be seen.
Traditionally, the Norns and Fates are the ones who shape the lives of heroes and mortals. They proclaim their destinies which, once heard, the hero has no chance of avoiding. While the High Matriarchs don’t have any grand, supernatural powers that lock heroes (or Aloy) into a set future, they do still have a massive amount of influence over the tribe. Its their word that dictates the tribe’s course of action and they oversee most major events such as namings and trials. They have the ability to banish or welcome back people into the tribe and as we see with Teersa at Aloy’s naming, they can even ignore past rulings if it suits their needs and agenda. Ultimately, they only answer to Tribal law and the will of the All-Mother, but even those aren’t always binding so long as they believe they are following the will of the All-Mother. That makes them incredibly powerful figures within the game and Nora society and for the most part, their wisdom leads the tribe well even if they don’t always agree on which path to take initially. It is their support (or lack thereof) which help to push Aloy at the start of the game and help her as she begins the next arc of her hero’s journey.