- Very fast sweeper
- Can hit very hard, especially after Bulk Up
- Ghost types in general
- Sableye/Mega-Banette - not only are Ghosts, but also have priority Will-o-Wisp
- Trevanant - also a Ghost, but resists Earthquake and often has Will-o-Wisp
- Most Defensive Pokemon not weak to Fighting can deal with this set. Some notable examples: Hippowdon, anything with Protect (makes High Jump Kick hurt the user), Quagsire, Milotic, Suicune
Despite all the cons it can actually be a very good set. The main con is that any of things above will force you to switch out, which negates your Unburden boost, as well as any Bulk Ups you happen to have used.
If you want to use it, I would suggest replacing Bulk Up for Knock Off, or maybe Sucker Punch. It does make you unable to boost your attack, but personally I feel the extra coverage is worth it, as it means you will be forced to switch out less.
The best way to use it as a late game sweeper, after the Pokemon that can wall him (i.e. Ghost types) have been dealt with.