It has never been officially established how matoran are created, only that Metru Nui is required to create them. It’s been one of the mysteries hanging over Bionicle for a while, and to clarify: I am glad it was never officially revealed. I love a good mystery, and furthermore, love trying to crack a good mystery.
I’ve been pondering this for a long time, have had a hypothesis in the works that I believe there is some evidence for, and fits in line with Bionicle’s overarching themes and ethos.
I’ve come to the conclusion that, in order to produce a matoran, the combined efforts of all 6 metrus would be required. Leave out any one of them, and production cannot go forward. All throughout Bionicle lore, throughout every year, from the sets to the stories to even the marketing itself, the idea of the 6 core elements working together has always been at the heart of Bionicle’s core message and philosophy. Unity Duty Destiny. Unity comes first, because it is the first step to achieving the latter 2 virtues.
A matoran body, of course, would have to be manufactured, the most obvious first step. This would likely be handled by the combined efforts of Po-Metru (with it’s industrial capacity) and Onu-Metru (setting up gears, problem-solving, blueprints, etc.). Perhaps Onu-Metru, with it’s vast Archives, would be able to grow and harvest organs for the matoran to use, although I’m a little dubious of that.
Now we have the body, but the matoran has no mind or soul. This is where Ko-Metru comes into play, and also my core piece of evidence to my theory. The main role of Ko-Metru is to watch the stars and grow knowledge towers, which in turn produce knowledge crystals. Now we know that knowledge crystals and memory crystals are often consumed by crystal climbers, and has been theorized to boost their intelligence.
What if those knowledge crystals could be shaped to form the brain stalks of matoran (which we know to be a form of crystal)? Think of it as the hard drive for matoran “programming”. This would make Ko-Metru, arguably, the most vital metru in matoran production.
Ta-Metru, of course, already produces masks which all matoran need, they just have another reason to do so, besides which they’d be providing alloys and materials to Po-Metru and Onu-Metru. That’s a lot of supplies being sent to and fro, which is where Le-Metru would come in, coordinating logistics so everything arrives on time (perhaps it is a process that is time-sensitive).
Ga-Metru’s role is perhaps the most interesting, as I don’t actually believe that they’d be that involved in the creation of matoran. Because there is a step after matoran birth: matoran integration. They may now exist, but they have entered the world knowing nothing about anything. This is where Ga-Metru’s vast education infrastructure would come into play, teaching and training up newly-formed matoran about history, the Three Virtues, law, culture, etiquette, etc. Metru Nui, and by extension the Matoran Universe as a whole, is a complicated place, and so there is a lot to cover after all.
Each matoran would probably develop their own personalities during this time, partly due to each crystal being unique, determining things like temperament, and other factors such as potential faults/tweaks during production and experiences during education. They’re progress would be monitored closely during their time at the universities so that it can be determined what occupation would best suit them. If they were not suited for anything in Metru Nui (or other settlements were in need of a large matoran influx) they would be sent somewhere else, most likely the Northern or Southern Continent. It would also go ways to explain why an entire district in Metru Nui is dedicated almost solely to education (something I always found odd prior to my theory).
Thoughts?