DIMENSIONAL SHIELD 
At first glance, this card may seem very strong. At second glance... it still seems very strong. And at every other subsequent time you look at this card, you can't help but smile and think,
I love this card. The Dimensional Shield is one of the most powerful stall cards this game has to offer, and is definitely one of the defining features of the element of Aether.
The basic jist of this card is this: it gives you 3 whole turns of immunity against the vast majority of forms of damage in this game. I guess a simpler way is to say what it does not block against. It does not defend against creatures or weapons with Momentum, poison damage, spell damage, or Unstable Gas damage. Although this may seem like a wide array of things, that leaves much more that this shield can block. ALL normal creature and weapon damage is blocked. Basically, 90% of the time, you are untouchable for 3 turns. This makes the Dimensional Shield one of the best stalling cards in the game.
This card is usually used in the mono-Aether deck. 6 of them are used in order to provide a wall of defense. Also, it is used in a Rainbow stall or False God deck although it is often replaced by Quintessence. Finally, a variety of duo- and trio- decks used this card, but it is in the mono where it really shines.
How do we use this card? Stalling and more stalling. Play one when you need time to set up an offensive or control scheme; it basically gives you 3 turns to draw cards and get enough quanta to unleash a deadly tactic. This can be seen in good use in False God decks, where a well-timed Dimensional Shield is often the precursor to a Fire Storm, Bonewall, and Quinted Otyugh. You can also use "chaining", in which you play a Dimensional Shield every THIRD turn. Thus, assuming you draw all your shields and have enough quanta to play them, essentially, you have 18 turns of imperviousness. Chaining shields is great in a mono-deck when you have 6 Shields; then, right when you are about to be killed, you can start chaining shields, giving you 18 turns to kill your opponent before your shields run out-plenty of time. Another strategy is to play a shield early in the game when there are no damage sources out, then continue to chain shields. If you are lucky, you can get an Elemental mastery. This is especially useful to rush decks. Finally, you can just play this shield when your opponent plays a lot of creatures out to simply prevent being killed.
Protect Artifact works really well with Dimensional Shield. If your opponent has a Pulverizer, Butterfly Effect, Deflagrations, or Steals, you can Protect your shield to make all their permanent control cards useless for truly impenetrable protection. PuppyChow designed a mono-aether with an Earth splash for just this purpose; I used a variant of it to win a tourney. It is indeed very powerful.
Shard of Gratitude gives you something to do when you are busy chaining Dimensional Shields. When you get down to a dangerous amount of health and start chaining shields, you can seal your victory by playing a Shard, healing you for 5 health every turn. With 2 Shards out, you can heal a total of 30 health after a shield. The Dimensional Shield and Shard of Gratitude combo is one of the best healing combinations in the game - the ability to heal without taking any damage is awesome.
Sundial is the other ultimate stall card in this game, allowing for 1 turn of stalling against even creatures with Momentum. With 6 Shields and 6 Sundials, you can stall for 24 turns - around the amount of turns before a 30-card deck decks out! This is obviously a great strategy. Combined with the fact that Sundials are very cheap make for an ultimate stalling wall.
QUINTESSENCE 
Out of all the Alchemy cards released, 1 for each element, it is in my firm opinion that this one is the best of them all. It is deceptively simple at first glance. All it does is make a creature untargetable, and it does so at a cost that is not to be sneezed at. So? So what?
The answer: So EVERYTHING. The sky's the limit! Previously, the only way to play untargetable (immaterial) creatures was: 1) Get Anubis. This requires a great amount of 2 different elements, the risk of having your creature killed, and general clunkiness. 2) Play a creature already Immaterial (namely, Immortal and Phase Dragon). Unfortunately, this is both very costly and very limited. The creatures do not have any skills and are only from one element. This is not to say that they are not useful; they are.
Quintessence changes all of this. Now, with a bit of aether quanta, you can immortalize any useful creature you want. And the options are nearly endless. Some strategies include quinting creatures with useful abilities like Otyughs and Mind Flayers. Others can involve quinting more offensive creatures, like Dragons or creatures with Growth. This is especially useful against decks with Parallel Universe in it, so that they cannot use it on your powerful creatures. Essentially, Quintessence negates creature control, one of the fundamental ideologies of this game. And that's powerful.
Quintessence is usually used in false god rainbows, because many false gods have creature control and Quintessence drops that flat. Otherwise, it is found a lot in mono- and trio- decks to stop creature control. Mono decks don't carry it around much.
Otyughs and other useful creatures rock with Quintessence. A Quinted Otyugh is a cornerstone of success for False God rainbows. Essentially, it's a creature that can kill many other creatures and cannot be killed itself. That's the power of Quintessence. You can't stop it once you put it on a creature.
Speaking of which,
Momentum is awesome with Quintessence. If a creature is both Immaterial and Momentum, then it is literally unstoppable. It is damage that will continue to hit your opponent, negating both shields and control. Just think about a Growth creature that is both Quinted and Momentum'd.
Mutations are great with Quintessence, too. Mutations often have VERY useful abilities not found in normal creatures, like Destroy or Steal. Quinting a mutation with Destroy is akin to a Protected Pulverizer - no permanent is safe. It is often in mutations that the true power of Quintessence really shines. No matter how powerful a creature, it usually has a weakness - it can be removed. And that weakness is almost fully removed with Quintessence - a very agile, versatile card that is all but necessary in a False God deck.
FRACTAL 
Fractal is one of the cards most recently introduced into this game. I admit, when I first read it, I was confused, too. I had no idea what it did or how it could be used. Then, I started experimenting... and I saw the light. Today, Fractal is one of the most powerful cards in the game, capable of crafting a multitude decks to suit any purpose in the game.
Essentially, Fractal generates copies of the creature you choose into your hand. One important thing you want to remember when playing it is a hand as empty as you can get it. That means that if you are to Fractal a Ray of Light, you want as little clutter in your hand as possible. You should play as many other cards as you can- other Ray of Lights, some creatures, some spells if you want - in order to get the maximum amount of copied creatures. The second thing you have to remember is cost. Fractal is a very expensive Aether card, so always play your other Aether cards before playing Fractal as it will drain all your
(and I learned this the hard way
).
Not only that, but the creatures you generate from Fractal appear in your hand, not the field. Thus, you need to have enough quanta to play these creatures. On the whole, you should target creatures that you can play. Usually, these will be very cheap creatures, but if you have a ton of
quanta, why not target an opponent's Lava Golem?
Despite all these shortcomings, Fractal is one of the most flexible and powerful cards in the game. Just think about it. Fractaling a cheap creature with good damage, like a Giant Frog or Minor Phoenix, results in an instant rush of fast damage. This is great for rush decks. Fractaling a more strategic creature, like Devourer or Scarab, results in instant control. In the case of the Devourer, you instantly have massive quanta control; massive creature control takes place with Fractaling Scarabs. And the possibilities never end! Fractal Ray of Light in order to fuel your Hope shield! Fractal Brimstone Eaters to generate
for Fire Bolts! Fractal Sparks for an instant blast of finishing damage! Fractal is perfect for a rush or control deck, and thus, it finds a beloved spot in many decks.
Fractal is usually found in a duo deck - one element being Aether for Fractal and accessory cards (Dimensional Shield, Lightning) and the other element containing the creature you intend upon Fractaling. Fractal has also found its way into many Rainbow decks for extra damage and the ability to Fractal your opponent's creatures. Trio decks also embrace Fractal, but Fractal is predominantly used in very powerful duo decks that are perfect for a variety of goals.
Devourer is excellent with Fractal. With Fractal, you can quickly generate a field full of Devourers, sucking dry the vast majority of mono and duo decks. The combination of Fractal and Devourer can utterly knock out AI3 and PvP decks, and combined with Drain Life, you can Mastery with it, control creatures, and deal damage to your opponent.
Ray of Light is also one of the more well-known Fractal combinations. Ray of Light is free, meaning that you don't have to hassle with Ray of Light casting costs. After Fractaling a Ray of Light, you can play a Hope shield for one of the most surefire defenses in the game. With a full field of Ray of Lights, no creature with more than 23 attack can hit you. Throw in some Light Dragons for offense and you have a fast deck with an unbeatable defense and fast offense. In fact, this deck is often used to farm False Gods, as well as PvP.
Dimensional Shields are good in collaboration with Fractal, also. When setting up a Fractal creature combination, playing a Dimensional Shield at just the right time can give you enough time to gather enough quanta in your non-aether element, as well as clear your hand for the path of Fractal.
All in all, Fractal is a card central to many decks that provides for a massive amount of damage, creature control, quanta control - you name it and Fractal does it. Truly, this is one of the most remarkable cards in the game.
Done.
