Essentially, if a player spends his DKP, the amount spent is subtracted from his decay for that week. If decay was supposed to reduce his DKP by 100 points, and he spent 50, his decay is only 50.
This encourages players to spend their DKP on stuff that is a slight upgrade, even if it’s not that 1 coveted item that everyone saves for that never drops, and would help the guild progress.
Naturally, this would mean decay would have to be calculated on the DKP a player has at the start of the week.

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