. fdsfWitherite is required to create the Mechanical Fusion Anvil in the Cataclysm mod, which is currently its only use. Though if you install Just Enough Items, you’ll notice no recipe for Witherite Ingots.
How to Get Witherite Ingots
The only way to obtain Witherite Ingots is by killing the Harbinger. This boss can be found within the Overworld, specifically inside the Ancient Factory structure. You must be prepared for a mechanical-styled boss with multiple attack styles.
We have covered how to beat the Harbinger in another guide, but it isn’t any more difficult than other bosses, such as Ignis. Bring a shield, plenty of food, and a Bow and Arrows, as the Harbinger can fly.
One way of defeating it is using the EMPs surrounding the Ancient Factory. When the Harbinger’s death laser attack charges these, they can be activated with Redstone, which will release an EMP pulse, temporarily disabling the Harbinger.
If you struggle to find the Ancient Factory or the Harbinger, craft an Eye of Mech. The recipe requires an Eye of Ender, 4 Iron Ingots, and 4 Redstone Blocks. Releasing this in the Overworld will lead you to the Ancient Factory.
Once the Harbinger is defeated, it will drop a Wither Assault Shoulder Weapon, as well as a block of Witherite. The block of Witherite can be taken into a Crafting Table (or the crafting interface inside your inventory) to give 9 Witherite Ingots in return.
Uses for Witherite
Witherite Blocks can always be used for decoration, but their primary purpose is to be turned into Witherite Ingots. These are used to create the Mechanical Fusion Anvil, which can upgrade equipment provided by the Cataclysm mod.
Six are required in total, as well as a regular Anvil and 2 Redstone Blocks. Four items can be upgraded inside the Mechanical Fusion Anvil: the Gauntlet of Guard, Infernal Forge, Ignitium Chestplate, and the Wither Assault Shoulder Weapon.
These are combined with other items, such as the Bulkwart of the Flame, Void Core, and the Elytra, to give new abilities. One example is the Void Forge, a combination of the Infernal Forge and a Void Core. Instead of dealing a knock-up area effect, you will summon a fan shape of Void Runes instead.