Why do alterations cost so much???
Augments cost a large sum of crystals/Tankoins because they provide extra bonuses to the turret/hull they are equipped on, and most of the time, have a large number of positives that outweigh the negatives of such equipment. For example, the "high-capacity ammo clip" augment for Hammer allows the user to carry an additional two shots in their clip, without any downsides. If such an "ability" was available for a much cheaper price (such as the old price of alterations), it wouldn't be fair for free-to-play Players, as they most likely couldn't afford such pieces of equipment, but pay-to-win Players, on the other hand, could afford them with ease, and dominate battles because of these augments.
You can find more information about augments in this Wiki article.
Hope this helps!
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