Right, time to throw my two cents in. Riolu has entered the field.
This little gem resides fairly low in NU usage, and I don't blame them. Riolu requires dedicated support and a fair amount of skill in order to work well, although he can hold his own against certain opponents or in certain situations as opposed to being a sitting duck the minute he screws up. Hazards are of course mandatory to unlock its potential. However, you may know what it does, but it doesn't necessarily make you prepared for it.