This is a meta deck and I do not claim authorship of it. I don´t remember the original source, so I uploaded it here to share what I am playing.
I am around rank 3 and trying to go up. My personal experience in the last days is as follows:
Abysmal matchups: Aggro Mage w/ Aluneth and Aggro Shamman. Those two decks have a partial boardless strategy of burning you with spells, and there is nothing that can be done about it.
Bad matchups: Control/Taunt warrior and Mill rogue. They are very rare nowadays, but if they run double Dirty Rat, there is a good chance they can fuck up the combo, even with the Simulacrum spare Aprendice. In the case of rogues, they can mill your deck, which has some reactive and slower cards.
Even matchups: Aggro/murlock paladin and Dragon Priest. They have a boardcentric strategy, therefore it is possible to control them with freezes and taunts. On the Paladin matches, sometimes they have a full board and Ice Barrier can work as pseudo Ice Block, since you can freeze their boards and be attacked only by the weapon.
Against the dragon priests, you have to be aware of the possibility of they silencing theyr frozen minions to pop a block or kill you. This is also true for silencing a doomsayer.
Good matchups: Control decks, including Warlocks, giants, etc. Cubelocks w/ doomguards do not fall under this cathegory, but I have seen less of them. Any deck that allows you to cycle trought your deck will die to infinite damage. One thing to keep in mind is that you run double Coldlight Oracle, which may burn warlock cards after a couple of their life taps.
As a general rule of thumb, keep anything that says "Draw" and throw everything else back. You don´t want any one of the combo pieces, since they are only playable on very late game, neither the secrets, since they can be draw and played by mad scients.
You should try to draw as fast as possible. The board freezes should be played when you:
a) Have a doomsayer to protect and whipe the board.
b) Opponent has lethal.
c) You have to get rid of a card in hand.
The OTK combo is having Anthonidas, 2 or 3 apprendices and 1 or 2 Molten Reflections. You need 4 Emperor ticks on the 5 cards, therefore it is possible to play him before having the full combo assembled (in fact, as soon as you have 4 combo pieces and can survive the pression, you should play emperor).
You should try to play your Coldlight Oracle before your Arcane Intelect, since in a desperate situation you can play them for free with 3 Apprendices to fish for final combo pieces. Another desperate move is playing apprendices facing a frozen board and protected by mirror images if you aren´t able to discount them beforehand, hopping for the oponent to be unable to deal with them.