I don't even know if the developers still update this game anymore, but a solution to the boorishness of the late-game, might be to add more tiers of gems, or even + tiers of gems, like the materials. It could make it more easier to catch up with the exponentially-growing defenses of the materials, and make it more rewarding for grinding for those specific gems. At a certain point in the game, you're able to get the highest-tier gem easily under a minute or less. So, if a developer reads this, please do something about it. :c
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