Spawn a Villager away from 30 blocks and spawn a Zombie at the End of the 30 Blocks and you will see the Zombie will be attarted with the Villager. Bush 10.0 MyTablet

'To Reproduce'
Spawn a Villager in a cave or anywhere else less than 40/50 Blocks
Spawn a Zombie far away from a Villager 20/24 blocks away
Look Closely the Zombie will be attracted and chase the Villager out in the distance.