Find a Trial Chamber
Defeat Breeze mobs to get Breeze Rods
Find an Ominous Trial Key
Use the Ominous Trial Key on an Ominous Vault
Open the Ominous Vault to get the Heavy Core
Craft a Mace with 1 Heavy Core and 1 Breeze Rod in a crafting table
Find a Trial Chamber
Defeat Breeze mobs to get Breeze Rods
Find an Ominous Trial Key
Use the Ominous Trial Key on an Ominous Vault
Open the Ominous Vault to get the Heavy Core
Craft a Mace with 1 Heavy Core and 1 Breeze Rod in a crafting table