[Worm Spoilers] About the creation and modification of shards.

I assume that there is a shard out there that can modify other shards to some extent. The entities are known to b able to modify shards and they are deciding weather or not to discard useless shards and modify current ones. I wanted to ask if in story do we se anyone who could possibly have the shard that lets them modify other shards, so someone who can change the powers of others.

How would this manifest in story? Any idea what kind of limits someone would have if they were given this shard and how the power would express itself?