

Why are two runes listed as her top drop? She has normal item drops like any other monster these can go up to the highest runes listed Ko on Nightmare and Lo on Hell.

This ability was enhanced and modified in v1.10, and in v1.11 she is now almost certain to drop at least one rune every time (1/64 chance of none dropping), and has the capability to drop up to six, though more than 2 or 3 is a very rare sight. Starting with the v1.09 patch, The Countess was given the ability to drop one or more runes almost every time she died.
