Support Ninetales/Vulpix
Held Item: Leftovers
Nature: Modest
Ability: Flash Fire/Drought (it doesn't really matter, and my Vulpix has Flash Fire, but I've heard Drought is nice)
EVs: 122 HP/82 Def/15 Atk/122 SpA/102 SpD
Flamethrower
Fire Blast/Energy Ball/Solar Beam
Fire Spin/Will-o-Wisp
Confuse Ray/Sunny Day
Flamethrower because it still does damage, for opponents with less HP.
Fire Blast for opponents with more HP, but Energy Ball gets rid of Fire type's weaknesses. I also threw on Solar Beam because some people like it.
Fire Spin/Will-o-Wisp for damage over time. Both are good, but I like Will-o-Wisp because it halves attack and lasts longer, but Fire Spin does damage at the beginning, which is kinda nice.
Confuse Ray just to be extra annoying, and it can really help. Also Sunny Day in case you can't find one with Drought and are too lazy to keep looking.
If you have this Ninetales in the front slot, it'll do a lot more. I hope this helps.