Spawns a blue fly familiar that will follow Isaac's movement with a 1-second delay and fires tears at nearby enemies.
Papa fly follows Isaac on a 0.66 second delay instead.
Papa Fly's tears deal Isaac's damage, and are fired once per second.
This item belongs to the Beelzebub set. Collecting three items from this set will transform Isaac into a giant humanoid fly.
Notes
Since Papa Fly's damage scales off of Isaac's own damage, any item that provides a massive damage increase (such as Ipecac or Polyphemus) will prove benefitial.
Synergies
Multidimensional Baby: Papa Fly will always shoot two shots due to both of them having the same movement delay.
Papa fly follows Isaac on a 0.66 second delay instead.
Beelzebub set. Collecting three items from this set will transform Isaac into a giant humanoid fly.
Ipecac or 
Polyphemus) will prove benefitial.
Multidimensional Baby: Papa Fly will always shoot two shots due to both of them having the same movement delay.
Pooter.
Beelzebub 
The Binding of Isaac: Rebirth
