...and I'm going to fucking give it to them. (Note: This submission is largely so I don't forget the details of this plan once I'm less pissed off.)
I can explain! Really! (Note: This is for my Demon Hunting Campaign set in 1640's Ireland, so here be campaign specific dragons.)
My take on Dracula for my 1640's Demon Hunting Game
What if potions and tonics had negative side effects? Potions of increased strength cause violent tempers, or damage joints. What if potions of dexterity caused tremors, or palsy?
What if they were addictive, and had withdrawal symptoms?
Could someone make a bad batch? No one use the brown strength potion!