Conversation so far:
What is the great white owl relating to Cassandra Nova?
On Earth-TRN342, Cassandra Nova has somehow survived for four thousand years and nearly conquered the world as the Great White Owl
who nearly conquered the world as the Great White Owl?
Cassandra Nova nearly conquered the world as the Great White Owl
Was Cassandra Nova the Great white owl?
Cassandra Nova was the Great White Owl
what does Cassandra Nova do while she is the Great white owl?
Cassandra Nova unleashed the Great Corruption and dropped entirely the Veil that separated the Main Reality with the reality of the Revenants, better known as the Mummundrai.

Question: Is Cassandra working with other people?
Self-contained rewrite: Is Cassandra Nova working with other people as the Great White Owl?