Arthropod Egg

Some civ servers add the ability to obtain mob spawn eggs by killing mobs with a sword enchanted with Bane of Arthropods (an otherwise generally useless enchantment).

Mechanics
Killing a mob with a weapon that has the Bane of Arthropods enchantment has a chance to drop a spawn egg item for the slain mob type. Each level of Bane of Arthropods increases the drop rate by 3%. The drop rate increases by 2% for every Looting enchantment level. A monster that drops a spawn egg will not drop any other loot.

Baby passive mobs will not drop spawn eggs, only the adult versions.

It is possible to get the spawn eggs of all passive mobs except for Snow and Iron Golems.