Incubation Mace

Weapon equipment — Common

Your Incubates have, "Vennen Allegiance: Create three additional Spiderling Eggs for each opposing champion and put them into their decks."

Changes: Incubate
Slot: Weapon
Rarity: Common
Set: Armies of Myth
How obtained: Set 3 Chest Loot

What it does is the game's own text; how it was obtained is from the owner's records.