Hmmm your levels are pretty low, I'd recommend dropping Vullaby and getting another Flying-type Pokémon like Sigilyph, found in the Desert Resort.
Another thing I recommend is not having more than one move from a given type at the same time. My Emboar had Ember at first, then I ditched it for Flame Charge, then I replaced Flame Charge with Heat Crash, and finally I replaced Heat Crash with Flamethrower. Then I added Flame Charge in place of Defense Curl because I no longer had Rollout, but only because Flame Charge is a lot different from Flamethrower and might be useful if I ever need to increase Emboar's Speed.
I recommend Vanilluxe over Cryogonal.
I wouldn't say Seismitoad is good, but Unova has no good Water-types, so you might as well use it. Unfortunately it doesn't learn Earthquake without a TM, unlike Swampert and Quagsire... People like Jellicent, but I used it and found it unimpressive. Good at taking hits, crap at dishing them out.
I also suggest a stronger Dark-type like Scrafty, Krookodile or Bisharp.
To be on the safe side, you need to be at least L50, and don't be shy of using legendaries if needed. I owned Ghetsis easily with a L54 Haxorus with Dragon Dance and Taunt. Cofagrigus was setup fodder, then I killed every single one of his Pokémon in one hit. (On a side note I caught Haxorus exclusively for that)