This is my take on Spiteful Hunter, I have been playing around with slightly different variations for a while on casual and between Diamond 10 and 5. The list is pretty flexible, but there are a few key cards that I wouldn't recommend playing without. This list is fairly competitive (I have a 74% win rate after 50 games or so) though a good chunk of those games were on casual, and most of my losses were on ranked. But I do think this deck has a lot of potential, and I will continue to update the list as I play more games and hopefully, this deck can bring me to Legend.

This list is pretty straight forward with a lot of the cards in here, but there are a few I would like to elaborate on.

• Spiteful Summoner. This card, along with Nagrand Slam and Call of the Wild are (obviously) the inspiration of the deck. They provide huge power plays throughout the game. One thing to keep in mind, don't pass the turn right after playing spiteful summoner, wait to see if you get an Al'Akir the Windlord or something. Also, calling the deck "Spiteful Hunter" might be a bit misleading. You can still win games even if you never draw Spiteful Summoner, and you don't always have to play her as soon as you can. Sometimes it is better to play Zilliax, or Deathstalker Rexxar instead. Also, don't underestimate the power of Nagrand Slam and Call of the Wild. These cards are in here to trigger Spiteful Summoner, but they are also very powerful and swingy cards by themselves.                                                                                                                                                                                                                                                                                                     
• Escaped Manasaber. I wasn't entirely sure of this card when I added it to the deck, but after playing with it some I think he is worth it. He lets us get Spiteful Summoner out on turn 5 without The Coin and also helps us play our big spells and Siamat a turn sooner. Also, the 3/5 body with Stealth isn't useless either.                                                                                                                                                        
• Stitched Tracker. We can't play Tracking, and Stitched Tracker is the next best. Although picking Spiteful Summoner may seem like an obvious choice, but it isn't always the right choice. This deck wants to play reactively, answering whatever our opponents play. Stitched Tracker helps both the consistency, and flexibility of this deck. Keep in mind what is in play right now, and pick whatever minion is most useful in this situation.                                                                                                                                                                                                 
• Imprisoned Felmaw. This card was the sleeper of the set. People called this card bad because it was random and slow, but it is crazy powerful. Even if it doesn't do anything until 2 turns after you play it, being able to deal 5 damage for 2 mana is a lot. And if you drop both of these guys early enough, it is likely game over for your opponent. If it hits face, then great you knocked off 1/6 of their health, and if it hits a minion 99% of the time the minion will die. This just does too much for only 2 mana.                                                                                                                                             
• Loatheb. Loatheb is an amazingly designed card. He was made roughly 5 years ago and is still very useful. You want to use him different in different matchups, but you always want to play him in a situation where you are ahead and want to stay that way. Against Warlocks we usually want to try and delay Plague of Flames or Defile for a turn, against [Hearthstone Card (Demon Hunters) Not Found] you have to predict when they will play Skull of Gul'dan or Metamorphosis and try and delay that. Against Mages you want to slow down their combo whether it be Time Warp or simply double Fireball. You have to know your opponents deck and be able to predict their turn. But as a general rule of thumb, play Loatheb when you have a good board and are afraid of it getting cleared.

General Strategy

For the most part this deck is pretty simple. You just play like any other midrange deck. Keep ahead on the board, continue to pressure your opponent, play big stuff with Spiteful Summoner, and then drop Leeroy Jenkins and punch the opponent in the face for lethal. The best way to understand the decks strategy is to just play a couple of games and get a feel for the deck. When you lose try and figure out why, and what you could have done better. Play around secrets (the five most popular secrets in Secret Mage are Counterspell, Flame Ward, Explosive Runes, Duplicate, and Netherwind Portal), trade when favorable and go face when you have to.                       

This deck is very strong against aggro decks because we can play a strong early game and continue to put out bigger threats than them in the mid game. But we lose a lot to decks like Cubelock who can play big stuff early and maintain a strong board for the whole game. This deck won't be good in every meta, but I think some variation of this deck will have a shot against any given deck.

Deck Variations

When facing different decks, you want to play different cards. This list is sort of in between the best list for fighting aggro decks, or greedier control decks. Here are some different cards you might want to try if you are seeing more of one deck.

Against Aggro

As I mentioned above, our deck is fairly strong vs aggro. We have strong early game tools, and plenty of threats going into the later game. But if you want to make the deck faster and give it a better chance against decks like Demon Hunter or Secret Mage then here are some cards to add.

• Glaivezooka. This weapon isn't very popular, but it is very efficient. It can kill 2 Battlefiends all by itself. And in the first few turns of the game, that +1 attack can be very helpful as well. 
• Alleycat. This card is a solid 1 drop that curves very well into Crackling Razormaw. And it is a big help when fighting for the board in the early game.

Cards to take out for these:

• Escaped Manasaber. While this card is pretty good value, having isn't too useful when we are trying to stay ahead in the early game.
• Siamat. While Siamat is a very useful and flexible card, he simply isn't needed to win games against faster decks. Being a 7 mana card, there are better cards we would rather be playing against faster decks.
• Leeroy Jenkins. When fighting aggro decks, we are on the back foot. Having a strong finisher isn't needed when we are the slower deck. We are going to beat aggro by out-valuing them through card advantage and making smart trades, not by dealing as much damage as fast as possible.

Against Control

Against control, we want to generate enough value to last as long as we can, but we also want to consistently put out big threats early. We kill them by using Spiteful Summoner and Escaped Manasaber to get big dudes earlier than usual, but we still have enough threats to survive a board clear or two and a Reno Jackson. We want to play for value, but also pressure their life total. If you are fighting a lot of control decks, consider these cards.

• Imprisoned Vilefiend. This card is good value for only 2 mana, and it is very useful for establishing a threatening board early.
• Spellbreaker. When playing against value-oriented decks, there will always be a good target for Spellbreaker.

Cards to take out.

• Dire Mole. This card is simply not that useful late in the game.
• Crackling Razormaw. We are taking out Dire Mole, our best 1-drop beast, so Crackling Razormaw loses a lot of value.

Other Tech Options

Some more cards you may want to consider depending on what you are facing.

• Eater of Secrets or Kezan Mystic. When fighting Mages, secret tech is quite handy. When fighting Aggro Secret Mage I would put Eater of Secrets, but against either Combo Mage or Control Mage, I thin Kezan Mystic is better because they generally have a fewer number of secrets in play.
• Gluttonous Ooze. If our warlock opponent plays Skull of the Man'ari on turn 5, we are probably going to lose. If you are fighting a lot of Warlocks then Gluttonous Ooze can win you the game. 

Cards you may want to remove for these tech cards: 

• [Hearthstone Card (Maiev) Not Found] Against Mages.
• Deathstalker Rexxar against combo decks.
• Springpaw Against Warlocks (or maybe 1 copy against Mages)

One other thing I would like to mention, if you own either Dragonbane, or Zixor, Apex Predator, I would highly recommend playing them instead of [Hearthstone Card (Faceless Corrupter) Not Found].

If there is anything you want to know that I didn't put in the guide, please let me know. I will continue to update the list and guide as I climb the ladder. I hope you enjoy the deck, and I wish you the best on your climb to legend!