In the beginning Makuta,Ekimu,and Karzahni descended upon the earth. Makuta created the land, Ekimu created Matoran and other life. However, Karzakni was driven to madness by his mask of alternative futures and was exiled. Makuta makes a deal with Ekimu that there will only be six tribes. Until the mysterious lighting tribe shows up and a war starts between the two brothers. Most of the Matoran would of been dead in a battle of such power. This got me thinking, How do Matoran reproduce?This is when I came to the idea of Matoran Molting. After a Matoran dies a new matoran is born from the ashes. The Matoran keeps the mask but does not keep the memories. This would be a great way to repopulate the island after large battles such as the battle of two brothers.
It would make sense for Mangaians, but unless you mean ashes metaphorically, it doesn’t make as much sense for other areas. Especially ice.