Istaria, Azorius Investigator

When Istaria, Azorius Investigator enters the battlefield, if Athena, Watchful Familiar is in
your graveyard, you may return it to your hand.
At the beginning of your upkeep, investigate.
As long as Athena, Watchful Familiar is on the battlefield under your control, Istaria, Azorius Investigator has vigilance.