It is believed that queens are formed when certain grubs don't develop as they should and grow into adults. Instead, they develop ovaries and the hive mind. No one knows what triggers such changes except the queens. But what is known is that new queens will not form from grubs until the old queen has reached the end of her lifespan as a mana entity. The new queens will compete with the power of their minds and wrestle control of the workers and soldiers from their dying mother.
This competition will continue until the queen dies. The grub with the strongest mind will have the most workers and soldiers. It will chase away the other queens while it inherits the central room and the infrastructure of the colony. It will gain a strong start in life by feasting on the body of its dead mother while the others will have to start everything from scratch.