Mob Essence

Mob Essence (MFR) is a greenish colored liquid produced by the Grinder (MFR)  that can then be Consumed in an Auto-Spawner to create specific mobs. It is also used to Auto Enchant items with an Auto-Enchanter.

Video
How to process mob essence to spawn any mob capturable with a Safari Net

Automating Essence Berries in the B-Team Modpack