"zoning"
Zoning in LoL is just a lane tactic, where you prevent your enemy from taking experience points. But this is achieved by letting their minions fight and kill your own, you can't kill your own minions. There's a really popular tutorial, with a memorable voice, done by "Shurelia" on
Zoning.
Although a good tactic, as the victim this is the most annoying thing that can happen since you are forced to stay and watch the unfairness. It also slows the game a bit.
To clarify, in DotA and HoN you can start attacking your own creeps when they are below 50% health, if you land the killing blow on your own creep, the enemy obviously get no gold and about half the experience.
That is certainly incomprehensible, at least for a LoL player like me. It destroys gameplay value, and it's just not fair.
Afaik, in LoL the only champion that can deny is Gangplank, by using one of his abilities.