Horel

Horel was a drug and poison created by distilling a freshwater lily pad plant called halfling's hand, also known as oxhrel, and mixing it in a certain secret proportion with powdered horseradish.

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The resulting substance was a green liquid, harmless to skin contact or ingestion. However, if a needle or a weapon was coated with horel and the substance entered the bloodstream, the victim started violently convulsing, which dramatically affected their ability to defend oneself in battle or perform a simple task requiring a steady hand.