I got my first legend ever last night using this deck. This is the version I played from rank 4 or 5 all the way to legend.
Didn't start tracking win rates until late into the season, so the sample size isn't as big as it could be.
Overall: 87-68 56%
Warrior: 9-12 43%
Shaman: 6-8 43%
Rogue: 0-1 0%
Paladin: 18-9 67% (More against secret, less against control)
Hunter: 20-14 59%
Druid: 3-6 33%
Warlock: 12-4 75% (more against zoo, less against handlock)
Mage: 8-9 47%
Priest: 11-5 69%
We are extremely heavily favored against secret paladin and zoo, which is why deck works well in the wild meta. We also beat priests most of the time. Patron Warrior is extremely hard to beat, as is Freeze Mage and any Druid.
Against Warlock, Paladin, and Hunter, also keep Fan of Knives
Against Hunter, also keep Sludge Belcher
You can play tempo or midrange, depending on the matchup and you and your opponent's draws. Sometimes you can come out fast and win early, but most games you will be fighting for the board. You also have a strong endgame if you draw N'Zoth. This deck is very good at clearing your opponent's board and making your own stronger, and you can crush Secret Paladins and Zoo this way! We're also resistant to clears, so against Freeze Mage your best bet is to just throw out all your deathrattle minions and pray he doesn't get all the freezes he needs.
Against aggro, especially Hunter and Shaman you need to protect your life total vigilantly, even making bad trades at times. There is no healing, but we do have 4 taunt cards (if you include Defender of Argus).
Against control, if you have an aggressive hand you can knock them out quickly, go for it! Your board is very resilient due to all of the deathrattles. You will frequently go into the late game against control, and that's where N'Zoth comes in. Try to plan ahead a few turns to make sure your N'Zoth will summon the best and biggest board possible. Try to bait out brawls against control warrior.
Cold Blood Mainly an activator for Egg, but can be used as removal or burst. I recommend only using one, the Defenders of Argus are usually better and are also activators for Egg.
Nerubian Egg This and Raptor are the core of the deck. You best opener is egg into raptor, even against a aggro opponent's fast start. It puts you so far ahead on the board it will be extremely difficult for your opponent to come back.
Sap Best against taunts and Sylvanas. Also Tirion of course. You could probably cut it to 1 if you really want to make room for something else, but I strongly recommend 2.
Undercity Huckster If you're looking for something to cut, this isn't a bad choice. I mainly play him because he smooths out my early draw, you really want to get something on the board by turn 2 with this deck. He doesn't benefit N'Zoth much, since you have many better deathrattles you'd rather summon, and he grabs junk from your opponent frequently. I mainly play him because he smooths out my early draw, you really want to get something on the board by turn 2 with this deck.
Unearthed Raptor The other core card of the deck. You'll almost always play him on turn 3 if you have him, even without deathrattle targets. Your primary goal is to keep the board under control in most matchups. The bright side is you will have a target for him 95% of the time.
Baron Rivendare I have cut him and added him again and again, and ultimately decided he was best for the deck. You might think he is a win-more card, but in this deck he frequently gains so much value that he wins the game for you. Many times, you'll just play him on a turn when you break a shredder or egg and get one extra minion, and he is still good even in this situation. This deck is so good at keeping the board and has so many deathrattles, that you will almost always find some way to get Baron to trigger at some point during the game. He's also good with Defender of Argus against aggro, he makes a nice wall. :) That said, if you are looking for a card to cut, he can be if it's your preference.
Defender of Argus Obviously, the ideal is to activate an egg, but against aggro, do not hesitate to drop him in between any 2 minions to protect your life. You must stop as much damage as possible against aggro! Can be cut if you want to try some other cards, just make sure you have activators for your eggs.
Xaril, The Poisoned Mind Another potential cut. The potions can really get you out of a jam sometimes, though. The bounce potion is generally one of the worst, but keep in mind that you can return a defender of argus and replay it. I've done this more times than I can count. The +3 potion also has tremendous synergy with the deck.
Dark Iron Skulker Another potential cut, depending on the meta. This guy doesn't fit the theme of the deck, but he is murder against hunters, zoo, and secret pld, which I was seeing plenty of. He isn't bad against other deck types, either, unlike another tech card, Eater of Secrets.
N'Zoth, The Corruputor If the game is going badly and you have him in hand, just try to survive until you can drop him and end it. If possible, you can try to avoid playing huckster or creepers in the late game, especially if you lost several shredders and belchers and sylvanas or sky golem. You will gain a full board with N'Zoth more than 95% of the time in my experience due to the huge number of deathrattles you have.
Other Cards to Consider / Replacements:
Abusive Sergeant Works well in place of Cold Blood or Argus, and makes the deck a little more aggro. I don't recommend him since the nerf, however.
Undertaker Another card if you want to go a more aggressive route. I found him to be too inconsistent, and a dead card late game, so I don't usually include him.
SI:7 Agent A staple in Rogue, and still very good in this deck. You can play one or two of him if you prefer it over some of the other cards.
Tomb Pillager Very solid replacement for Xaril if you don't have him. Also just good in general, but we already have lots of 4-drops, especially with the Defenders of Argus.
Sir Finley Mrrglton The rogue hero power is awesome in many matchups, especially secret paladin, but Finley can be really good sometimes, and gives you a 1-drop if you are going a more aggressive route. I personally prefer to leave him out.
Loot Hoarder A fine replacement for Bloodmage. Another Undercity Huckster in place of Bloodmage is also good.
Huge Toad A more aggressive alternative to Huckster.
Eater of Secrets Strong card in the lower ranks while climbing against all the secret plds and hunters and freeze mages, and still decent in higher ranks. I cut it for Dark Iron Skulker because it is good against most of the same decks, but also fine against most decks in general. It's best against secret paladin, but you will be crushing them most of the time anyway.
Cairne Bloodhoof Good replacement for Sky Golem. I was running Cairne for a long time, but overall Sky Golem gets slightly better minions on average, and the 6 attack on sky golem has proven to be very useful. If you prefer consistency, go with Cairne. Over time, you should win more with Sky Golem though.
Antique Healbot If you're laddering and having trouble staying alive to kill aggro decks, a healbot is always a solid choice.
Barnes He usually gets something good, but the 4-drop slot is already crowded. Good in place of Xaril or Baron Rivendare if you want to give it a shot.
Journey Below Good on turn one, and good later to get you just the deathrattle you need.
Thanks for reading, hope you enjoy this deck as much as I did and good luck! :)