Now that you have plenty of Demon Will in your Tartaric Gem, it's time to explore what happens when you unleash it upon the world.
First off, you'll need to get Will into the Aura. Next, you'll need to make a Demon Crystallizer.
This will slowly consume Demon Will from the Aura to produce Will Crystals. The first spire costs 100 Will to form, and all subsequent spires cost 45 each, but can be burned for 50 in the Demon Crucible, for a net gain of 5. The largest Crystal Cluster can be up to 7 spires.
If you have more than 512 total Will in your inventory (Across any number of Tartaric Gems and of any one type), you can harvest these crystals by right-clicking the spire with an empty hand. This will remove all but the central spire.
However, if you do not have enough will, really need that central spire's Crystal, or are just in a hurry, you can harvest the whole lot with a pickaxe.
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5 will per harvested crystal isn't a particularly impressive haul, but the above rituals (alongside Will Catalysts) should allow you to boost and automate their production for some impressive gains.