Freeze. With other status you can plan and play around it. Confusion can be cured by switching. Sleep can be blocked or you can use Sleep Talk and the Pokemon that commonly use sleep moves are well known. But you can't plan for or counter freeze. I posted a video recently where the opposing Greninja froze my Quagsire on the first turn, and Quag remained frozen until fainting 4 turns later. But as if that's not enough, Greninja then froze my Xerneas that had + 2 Spdef and eventually haxed out a victory over it as well. There is simply no way to beat luck like that.
Confusion. I swear, when I use a confusion-inflicting move, it never works.
When the opponent does, my Pokemon keeps hitting itself.
This. This so freaking much. The other statuses are either too uncommon in my playthroughs, or have workarounds that make them less threatening. So it was down to Paralysis and Confusion. Paralysis lowers speed and may keep you from moving. It cripples sweepers, but it doesn't hurt tanks and normally slow moving Pokemon as badly. No one benefits from confusion, though. The Metagame may revolve around switching, but I like to tough it out, only switching between Pokemon or after mine get KO'd. And even if Paralysis can keep you from moving, at least it doesn't make you hurt yourself. Those ducks have been the bane of my existence for a long time, and I utterly dread seeing my Pokemon get confused. The RNG likes to have a field day with me when that happens...
I am Xashowd, the Nocturne Zephyr! Official Darkrai of the Pokemon X/Y Boards. 3DS FC: 3695-0746-1582. Xashowd. PM me if you add me.