From Pluralpedia, the collaborative plurality dictionary
spawner (n.)
Other formsSpawnmate
Applies toheadmates
CoinerThe Nathyl Polyplex

A spawner is a member who has a tendency to "spawn" members around them, not through intentional creation and not necessarily due to stress, they simply happen to often form members based on, or attached to, them.

Examples of this include members who have many facets that hold aspects of their identity, or a member who often introjects doubles of themselves or forms snapshots.

This can be a role, type, or just a descriptor, depending on how the member wants to use it.