Hearthpwn

• Arcane Artificer - A surprising star in this deck, the artificer is an amazing card that often is underestimated and ignored on a board populated with other intimidating elementals. Not only is he a utility recovery tool, he's also a valuable way to maintain your elemental synergy on turns where you'd otherwise need to prioritize playing defensively and would lose out on it.
• Pyros - A common face in elemental mage lists, Pyros makes himself known here as well. The added benefit of Pyros in our deck, however is - you guessed it - synergy with Leyline Manipulator. Pyros' traditional weakness of being a very slow, basically vanilla minion are offset by the cost reduction, allowing you to weave in other actions or surprise your opponent by bringing him back early to secure your position.
• Shimmering Tempest - A weak tempo card whose main purpose is a means to an end, much like Loot Hoarder. It maintains our elemental synergy for coming turns, provides a random spell for our cost reduction effects, and trades reasonably well with the 1/2's and 1/3's that populate constructed these days. This card is even useful lategame with Jaina in play as ping fodder and pseudo card draw.
• Leyline Manipulator - The icing on the cake for this deck, the Manipulator turns the value of your random card generation to insane tempo via the cost reduction of not only spells, but generated minions as well through Pyros and Servant of Kalimos. In this deck I generally play it as a combo piece for use with 3+ generated cards, but it can make a powerful case as an on-curve play with the right hand texture.
• Frost Lich Jaina - Jaina is arguably the most defining card of this deck, since without this card the deck loses much of its inexorability, recovery and threat in the late game. Jaina is your single biggest win condition unless you manage to get a crazy amount of burn from your random effects.
• Tar Creeper - Tar creeper is just an all around good card for its cost and remains relevant at nearly any board state. Staring down aggro? Creeper. Juggling Jades? Creeper. Messing with midrange? Creeper. The dude is just too tanky for efficient point removal and has to potential to heal you for far more than his own health total. The fact he has reduced attack on your turn is an amazing way to bump and manipulate health totals to net more elementals later on.
• Arcane Tyrant - Inserted as a way to maintain elemental synergy after a major control turn involving Blizzardor Flamestrike. It also makes Deck of Wonders less passive to play, since you can develop this guy for free off of the back of it. If I had a second copy of this card I would cut deck of wonders in exchange for a second copy of this.
• Servant of Kalimos - One of THE reasons you play elementals in the first place, the servant of kalimos is an excellent way to find additional minions to fit your game plan. Choosing otherwise greedy or expensive minions is counteracted by the cost reduction granted by Leyline Manipulator, who is also a discoverable option from this guy, by the way. Anomalus for large threats, geddon for aggro, pyros for control, MORE servants for tempo...this guy is a one man swiss-army knife.
• Blazecaller - BlazeCaller is a powerful, flexible card in our deck that both provides and demands an answer for many scenarios we may encounter. Primarily included as a means to combat heavy removal decks that seek to deny Frost Lich Jaina's hero power, our normal means of closing out games. This card is also a reasonable answer to Carrion Creeper, Cobalt Scalebane and Bonemare.

• Lesser Ruby Spellstone - A more tempo-friendly version of Cabalist's Tome that generally comes to full bear right as you would otherwise run out of hand size. This card is an amazing pairing with Leyline Manipulator. Even random "trash" cards like Shatter find a use in this deck with the abundance of freeze effects granted by our Blizzard and Frost Lich Jaina, not to mention other freeze effects generated via spells and minions like Glacial Shard, Frost Elemental or Ice Walker.
• Primordial Glyph - It's very often that the random spell created by this card is not only perfect for your needs as a slower deck, but if it's paired with Leyline Manipulator it usually costs three or less.
• Arcane Intellect - AI is here as a way to help our consistency, since this deck does rely on small, self-contained combos and can lead to small hand size once Leyline Manipulator's cost reduction hits. Since you have to play your elementals and spells wisely together, drawing into more of one or the other is often a crucial point of success in this deck.
• Ice Block - Standard and staple in pretty much any mage deck, ice block is here to avoid getting bursted generally around the time you're trying to develop Jaina and begin your snowball to victory. Played well, you can pretty successfully play keep away with your second (or third) iceblock with the help of jaina's elementals and Arcane Artificer.
• Volcanic Potion - A standard answer to a token problem when playing as a slower deck. Call to Arms and other token flood tactics that are dominant right now have real issues with this card. Even denying the divine shield value for Rallying Blade or Flametongue Totem is important, softening them up for successive removal and preventing advantageous trades into your big-butted minions.
• Polymorph - This deck lacks consistent ways to deal with singular large minions like edwin or big priest deck strategies. Polymorph has always been the traditional way to wipe the smile off their faces. It's also useful against key minions like Fal'dorei Strider, Astral Tiger, Rin, the First Disciple, Carnivorous Cube, etc.
• Blizzard - Timeless and Classic. Stall and Deal 2. This card is a fantastic way to telegraph to eager board-based decks that you don't have an answer and bait a punishable extension on the board with your unpredictable removal. Since our board pressure is relatively low, it also behooves us to freeze a board to push face and potentially force awkward trades with our big-butted water elementals, forcing your opponent to freeze their minions yet again and open themselves up to advantageous pings. The freeze aspect of the spell is particularly useful, since it enables Shatter, an otherwise dead card from hand.
• Flamestrike - One of mage's most iconic signature cards, Flamestrike comes to call here as a way to put the last nail in the coffin of your opponent's board aggression or enable stabilization through use of minion trades, pings and other spell effects.

Chaos Package:

• Shifting Scroll/Babbling Book - Shifting Scroll can be argued to be a worse Babbling Book, since it doesn't provide a body and doesn't synergize with Leyline Manipulator's cost reduction.  However, what it lacks in those aspects it more than makes up for in flexibility. Season to taste.
• Deck of Wonders -  Usually until the mid-late stages of the game your board presence is relatively passive and any subsequent board catastrophes are likely to effect your opponent more than yourself. Any other adverse effects like buffs to the enemy board can simply be stalled or outright removed. It's also a wonderful way to slant your results if you discover a copy of Dragon's Fury later in the game when you may have drawn most, if not all of your heavy spells.
• Yogg-Saron, Hope's End - This deck has enough ridiculous spell generation and stall to support Yogg-Saron, if you truly wish to embrace the random  aspect of this deck. Not the most competitive option by far, since it's not uncommon that this deck has to deal with hand management and yogg can easily burn valuable cards. But hey, don't let your memes be dreams.

Elementals of Note:

• Anomalus - Anomalus is a card typically ignored and brushed aside as simply too slow to be effective or counter-productive in an elemental list, since such lists are minion heavy and wiping your own board is generally a bad idea. But the interesting thing about anomalus is that, in this deck, it's not that hard to play him proactively and still feel good about it, since, until we begin to snowball with jaina we don't usually have a strong board to feel bad about wiping. Consider adding him if you're fighting slow, heavy decks like any if the Big or Jade Archetypes who have minions that most of our AoE spells don't effectively clear.
• Baron Geddon - Baron Geddon was once staple to many classic control lists, since aggressive decks didn't often have minions durable enough to survive one or two pulses from him. The added bonus is that Geddon acts like a Spirit Lash on crack with Frost Lich Jaina in play, creating the potential for absolutely insane health swings, which are extremely important in the aggro matchup. Geddon does have his weaknesses, since he's relatively fragile at 5HP, but at the end of the day he's still an aggressively statted minion that can either clear aggressive boards and force removal from slower decks.
• Steam Surger - This card is a more aggressively statted minion that's quite fragile, with the added benefit of creating a spell that can be reduced by Ley-line Manipulator. This card is more in line with an aggressive iteration of the deck.
• Fire Plume Phoenix - This card isn't a bad card to consider for a budget iteration of the deck.