While talking with a few friends, we realized that there weren't really any "poison" themed AD weapons. Just spit-balling here, but maybe adding an AD item that does damage over time (maybe on crits like van damm's pillager, or just a straightup poison)?
There are two ad items that do deal damage over time actually, wicked hatchet
, and it builds into the second item, Lightbringer 
, they both cause a bleed on crit. Although, Lightbringer is only available in ascension, and hatchet is only available on twisted treeline, and ascension. They were removed from SR because if they lowered the damage the items were useless, but if they didn't lower the damage it was over powered. That's probably why you haven't heard of them.
ummmmmmmmmm....
man, this would be annoying
