Calculates total shard / frag cost to upgrade an item from its current enchantment level to the desired one. Works for every shard and frag type in the game.
Low tier items gain +1 to the per‑enchant increment — not a flat ×2. For most stats (Light, Poisoning, Cast Prob., etc.) that means each successful enchant adds +2 instead of +1. For Endurance and Experience/Gold frags it means +3 instead of +2.