Drops are static. They don't improve the more you kill. So if something says 1:100 doesn't guarantee that you'll get it after 100 kills. It means it's the same 1 in 100 chance on each and every kill.
When the day becomes the night and the sky becomes the sea, when the clock strikes heavy and there’s no time for tea; and in our darkest hour, before my final rhyme, she will come back home to Wonderland and turn back the hands of time.