wrong forum I assume.
She can drop up to Lo, though the odds are very low - the odd increase with more players in the game.
If you want to have good odds, she drops up to ist with high chances - best run solo.
If you want to find hr's, countess ain't your best target IIRC, You're better of in cows or alvl 85.
actually, there isn't a good place to find hr. They are that rare they almost never drop, not even at the best target.