Short answer:
Remember the dreaded "Too Expensive!" message? Apotheosis deletes it. apotheosis 1.12.2
Every technical Minecraft player knows the pain of building a mob farm only to have poor spawn rates due to light levels or location. Apotheosis 1.12.2 introduces a robust spawner modification system that turns the humble Mob Spawner cage into a factory of death and resources. Short answer: Remember the dreaded "Too Expensive