1. 20x Alcohol Processing Efficiency
Your body processes alcohol with hyper-rapidity, requiring you to consume 20 times as much alcohol as before to achieve the same level of drunkenness. If it took 8 shots to get you drunk before, it will now take 160.
2. 0.2x Alcohol Processing Efficiency
Your body processes alcohol as fast as molasses on a cold day, requiring you to consume 20% as much alcohol as before to achieve the same level of drunkenness. If it took 8 shots to get you drunk before, it would now take less than two (1.6 shots to be precise).
EDIT: Presume that neither option would raise or lower your current level of danger associated with alcohol consumption.
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