After contact several Sivanas across the multiverse, Dr. Sivana from earth-5 to create Sivanaday from suspendium. However the Sivanas defeated themselves because their own malicious nature.
This cheating behavior would be the cause of their downfall. First they try to takeover diferent earths, on the run with the Marvel family after them. Under the command of Lecter Sivana and using robot armies to take over the Multiverse, the Sivanas again betrayed each other by send every member to an earth where they would be for sure defeated.
Known Sivana's of the Multiverse:
Several others unnamed Sivana's including a Luchador styled Sivana, a baby Sivana, a mustache Sivana, a goatee Sivana, a punk Sivana.
Is supposed than the Legion of Sivanas is a multiversal avatar of the Gentry member Demogorgunn.