It seems that when a mob is killed from the fire (DOT) of the fireball it doesn't (or rarely) drop items. Mobs which seems to be particularly affected are slimes and enderman. Skeleton and zombie seems to work well.
Item seems to have a greater chance to drop when mobs are kill with the initial damage of fireball.
I might be in the error.
Item seems to have a greater chance to drop when mobs are kill with the initial damage of fireball.
I might be in the error.