Isochron Scepter: this card works amazing with Turbo Fog. Basically allowing infinite Fogs, this locks down your opponent for two mana every turn. Get a Dawn Charm equipped to it and you can also counter incoming burns or Thoughtseize's.
Jace Beleren: This card is an amazing second win condition. Acting as a Howling Mine, he also packs an ult that seals an opponent's fate of decking out first.
Emrakul, the Aeons Torn: some of you are probably cringing at a dollar card getting switched for a 50 dollar card. But there are a lot of advantages. Unlike Elixir of Immortality, Emrakul will put the graveyard back into the library for free. While the loss of life gain can hurt and feel dangerous, the second reason is also important. If your opponent manages to negate your mill and have a way of recycling their graveyard too, they will not survive Emrakul when he is hard cast. Next to no one can. So as a last resort win condition, he takes the prize of being literally unstoppable.
Shelldock Isle: so while having a land enter tapped might be taboo to some, it can fish an extra Fog out of your deck for emergencies and cast Emrakul fairly easily if your lucky. Some actually run two of her because of this card.
Gideon, Champion of Justice: so this is a game two or three win condition. If your opponents locking your mill down or blowing up your enchantments like cannon fodder, Gideon can win the game before having to bide your dangerous time for Emrakul. As a planeswalker he is a lot harder to kill than an enchantment and psychs your opponent out by saying "oh I can't win with mill? Then I'll smash down the front door and take you down with creatures"
Luminarch Ascension: An alternate win condition for against those fond of personal Hexproof.
Leyline of Sanctity: Because your fond of personal hexproof. Helps against Burn and Thoughtseize type spells.
Pithing Needle: sometimes people run planeswalkers or a number of creatures that pose issues to a turbo Fog deck. Name them off and deal with them latter.
Supreme Verdict: An uncounterable Nuke is the best kind of Nuke. Plus it’s one of the cheapest mana cost board wipes in the game.
Swan Song is a powerful one drop counter with perhaps the greatest drawback imaginable: give your opponent a 2/2 flying creature. However, this is a Turbo Fog deck. we don't care about their creatures. The unique style of this deck allows you to run this powerful card and ignore the side effects.