Sorceress Sellen, the Graven

{u}{b}, sacrifice another creature: draw a card.
When Sorceress Sellen, the Graven dies, if it didn't had a Puppet Counter, return it to
the battlefield under your control and put a Puppet Counter on it. If it had a Puppet Counter, transform it instead.
'I was exiled from the Academy of Raya Lucaria, as a reviled, apostate witch. Do you
still wish to learn from me?'