The scalar values (80% for legendary, 70% for exotic, 50% for Imprecation) are crucial multipliers that determine the magnitude of the power level increase during infusion. These values have a direct impact on resource management within the game, influencing how players strategically upgrade their gear.

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https://www.reddit.com/r/DestinyTheGame/comments/3pmown/update_from_roger_wolfson_on_my_infusion/