Trundle bite bug
If you Q a minion with Trundle and the animation of the Q goes off, but the minion dies before the Q hits, you lose the Q and all hit-on effects are placed on your next basic attack. I think you get the Q passive even though you miss as well, but it never hits. Nasus' Q resets to next basic, so i guess it should be the same with Trundle?
Don't have a screenshot, but i think you get the point.
With love from a Trundle player climbing his way to plat ;)