Oil of Agony

Description
Prepared by a secret process, known only to those slaves of the Giant-kings who toiled in the arena, oils such as these were used to subtly influence the outcomes of arena combat. This oil, when coating a weapon, causes additional pain with every blow, until the coating has worn off. The downside is that the oil is acidic and eats away at the weapon over time, rendering it brittle and much more likely to break.