Imposter Doctor Iosefka

When Imposter Doctor Iosefka enters the battlefield, you may search your library for
a card named Iosefka's Bloodvial, reveal it,
and put it into your hand.
{u}{b},{t}, Sacrifice another nontoken creature:
create a 1/2 blue Celestial creature token.
When Imposter Doctor Iosefka dies, create a
Third of Umbilical Cord token.