Hearthpwn

Intro
This is my first published deck (suggestions welcome)!  It is difficult to be totally original in a world with a huge player base such as this... but I think this is my first "mostly original" deck.   It is a mash-up of Quest Paladin, Mech Egg Paladin, and Undatakah Paladin. I wanted to publish it now so people can try it before rotation happens.  It's crazy fun to play, and can definitely yield a +50% win-rate at the hands of a smart player who knows the meta, due to the excellent card synergy.

Some general bullet points about the deck:

~The deck is "anti-hard removal."  There are so many "must kills" in this deck, that by the time you use Da Undatakah in late game, they most likely are out of hard removal options.

~The deck is "anti Mind Control Tech," because you are typically running with 2-3 powerful minions on-board, and do not need the fourth to be threatening af.

~The deck is built to have multiple win conditions due to a plethora of card synergies.

~At it's core, you are using Mech-synergy as the bread and butter.  Kangor's Endless Army refills your board.

~Wedged within is the Da Undatakah + Immortal Prelate + Primalfin Champion + Mechano-egg deathrattle combo for late game fuel and for quest completion (you never run out of cards if done properly).  I use only ONE Immortal Prelate, because 1) with two prelates, your buffs are diluted between them (it is better to stack 'em all on one Prelate), and 2) the goal is to create an Undatakah that shuffles into the deck w/ enchantments, returns buffs to your hand, AND summons an 8/8 robosaur.  It won't always go this way, however, more on this later...

~Buff spells exist for board control via your minions, and quest completion.

~Uses three sneaky copy minions to ensure your buff spells (and/or your quest) get their mileage.

~Experience the thrill of your opponents' "Wow" emotes when you drop a completely unexpected Prince Taldaram (the "honorary" third Faceless Manipulator of the deck).

~Massive healing potential with Crystalsmith Kangor, combined with Zilliax and x2 Chillblade Champion.

~Rogue is the deck's worst match-up (vanish + sap remove magnetic upgrades and spell buffs).

The deck does not fit in the classic paladin archetypes, necessarily.  It controls the board, but is not "Control Paladin" in the sense of using removal spells.  It can totally OTK another player, but is not a strictly OTK deck.  It has mid-range beefiness, but keeps power into the late-game, and even plays into the fatigue game.  It has the Paladin quest, but is not focused on completing the quest by any means (You can win without it... the quest is the jelly on the PB&J sandwich, not the bread or the peanut butter).  The deck has multiple win conditions, depending on card draw, and your own decision making.

So I'm calling this deck "Quest Deathrattle Paladin,"  because that seems to be the best description.  The name highlights the fact that this deck uses heavy deathrattle synergy in order to keep you from running out of resources, both in hand and on board.

Strategy
Mulligan:
~Crystology is the best card to have in your opening hand.

~Keep your quest obviously.  Whether you play it first turn or not depends on your opening hand.  Sometimes you will wait until turn two or three to activate the quest, and play Glowtron first.  Just make sure you activate it before casting your first spell on a minion.

~The deck has MANY synergies.  There is no single opening hand/card you are shooting to obtain.  In general, seek a good opening mana curve (e.g. a 2-drop, a 4-drop, and 5-drop), seek no duplicate cards, seek to have one spell (sans the quest).

~Don't open the game with all spells in hand... you need minions on the board before you can buff them.  Also, don't freak out about summoning Galvadon.  Completing the quest is merely icing on the cake, not your primary goal.  It'll complete itself in time.

~It's okay to mulligan Da Undatakah, he isn't very useful early game anyways.  He is your late game, anti-fatigue, value-machine. Your ace-in-the-hole. I usually win (or lose, lol) before I even get to him.

~It is sometimes a good idea to keep Spikeridged Steed in your opening hand, because of how much guaranteed value the card holds on turn 6, especially if you can drop the egg on turn 5.

Early game:

~Use Crystology to pull out Primalfin Champion, Immortal Prelate, Crystalsmith Kangor, and the Glowtrons.  Primalfin is the best early game play, because you can buff him and get the spells back right away when he dies.  Crystalsmith is the worst early-game play (you aren't that hurt yet)

~Immortal Prelate keeps all enchantment buffs when he dies and is shuffled into the deck, which is AMAZING, and is great for early game control, but keep in mind if you go mega-nuts on buffing him, 1) You might not draw him again right away, and 2) Cards like Sap, Vanish, and Freezing Trap will strip Immortal Prelate of said buffs, and now they've gone to waste.  It is better to give him some buffs and then let him die to acquire the deathrattle for Undatakah.

~Playing Glowtron early is a risk, because it can water down Kangor's Endless army if it dies unmagnetized.  But sometimes this is the risk you take to maintain the board in the first couple turns.

~Using Sound the Bells on Primalfin Champ is a great move... e.g. if you play Sound the Bells on him twice on turn 4... you get two more of them in your hand when he dies. VALUE! VALUE! VALUE!

~If you have Potion of Heroism in hand, it can help your early game minions survive another turn until you can start dropping eggs, or magnetizing mechs.

Midgame:

~Turn 5 is egg time 90% of the time.  They won't normally try to kill it for obvious reasons, and for obvious reasons that is especially excellent for us.  It is a good idea to save buffs for an egg.

~Now is a good time to use Blessing of Kings.

~One of the best combos is: turn 5 egg -> turn 6 Spikeridged Steed -> turn 7 Faceless Manipulator (or Prince Taldaram).  This will give Undatakah two mechano-egg deathrattles, if hey both die, which mean either: 1) He won't shuffle back into your deck, or 2) He won't return spells to your hand.  In this scenario, we prefer the latter option, but at the end of the day, if you are still going to lose in late game after popping out two 8/8 Robosaurs, you probably were going to lose anyways, and it's time to analyze your misplays.

WHY FACELESS MANIPULATOR AND NOT CARNIVOROUS CUBE?

Well you see, Carnivorous Cube does not synergize AT ALL with Da Undatakah and I highly recommend not putting it in a deck like this.  Plus, Faceless Manipulator gives you instant gratification, which the cube does not.

~In mid game, magnetize your mechs, keep control of the board, copy important minions with our three copy minions.  Use A New Challenger if you need taunt.

~NOTE WELL:  A New Challenger can summon Windfury Harpy, which is a great choice if you plan to go face on the next turn, and an even better choice if you can buff it next turn for lethal using Blessed Champion.

~It is usually not a good idea to play Galvadon the turn after you receive him.  If you hold him in hand for a bit, you are more likely to catch your opponent off guard.

~Use some healing via Zilliax or Chillblade Champion if you must.

Remember: The focus is on controlling the board mid game, not on completing the quest. The quest eventually completes itself.  It is no good to leave yourself vulnerable by wasting all buffs on a single minion just to get Galvadon sooner.

Late Game:

~Be aware of cards like Psychic Scream, Volcano, and Twisting Nether.  You must avoid going into top-deck mode.  Exercise some restraint.  Hold some resources back just in case.  Now is the time when people will try to steal your ultra buffed minion with Mind Control Tech, so consider that before you play that fourth minion.

~By this point, you should have acquired at least 2 out of the 3 target deathrattles for Undatakah.  It is okay to play Undatakah on turn 8 if you only have 2 deathrattles for him ONLY if he has Immortal Prelates' deathrattle.  If you play him without Prelates' deathrattle, you have just wasted him because he won't shuffle back into your deck, and you didn't play him at full value.

~Now is the time to start eyeballing which minion will receive the Blessed Champion buff, to double their attack, if you are close to lethal.

~It is a good idea to save at least one Sound the Bells! for when you have 10 mana crystals, so you can use it 5 times.  This play can lead into a follow-up turn where you use Blessed Champion for lethal.

~Now is a good time to think about dropping Galvadon, if you completed your quest, and haven't yet thrown him on the board.  In late game, it is less likely Galvadon will be the target of AoE (you pretty much are always offered "cannot be targeted by spells or hero powers" as one of the 5 adaptations).

~It is best to drop Galvadon behind a taunt wall.

~Galvadon is a FANTASTIC choice for Faceless Manipulator or Prince Taldaram, UNLESS you are concerned about Twisting Nether, or Psychic Scream.  Vanish is less concerning, at this point because now you have two Galvadon's in hand, which means you can play both next turn (at 10 mana) and give one taunt and poisonous and +health, to help the other survive with windfury and +attack.

~Kangor's Endless Army will refill your board at a crucial moment, when you need it.

~Now is the point in the game where you can pair Crystalsmith Kangor with Zilliax or Chillblade Champion, and buffs, to heal all the way back of to 30.  It is best to play Crystalsmith behind a taunt wall, if possible.

Fatigue Game:

If you've made it this far, and played your cards right, congratulations!  You've most likely won the game unless your opponent is running a late game combo deck such as Mecha'Thun, Shirvallah Holy Wrath, Archmage Antonidas, or an Armor Shudderwock!  Why?  Because you most likely have a buffed Immortal Prelate and a buffed Undatakah which will continuously be drawn back into your hand, while the opponent has depleted all of their main resources!

If you used Faceless Manipulator or Taldaram to copy either of these cards, then you have 3 immortal cards cycling into your deck and hand.

yYou won't always win in fatigue mode, but considering that you never run out of at least one card to play, the odds are stacked in your favor.

In general, though, try to win before fatigue mode ;)

Possible Substitutions

Glowtron can be substituted for Righteous Protector.

Prince Taldaram can be replaced with Bronze Gatekeeper(s).

Kangor's Endless Army can be replaced with Blessing of Wisdom or Divine Favor (extra card draw to make up for the lack of board-refill).

Primalfin Champion can be replaced with Meatwagon or Silver Vanguard if you are looking to perform the Undatakah instant-summoning combo.  Just be aware that Silver Vanguard has to be played AFTER Undatakah is in hand or else you'll summon him too early and his battlecry won't trigger, effectively ruining the card.  These substitutions are nice if you don't have the paladin quest.

HAVE FUN! I hope this deck/deck-style provides entertainment for someone.  I cannot stress enough how much fun it is buffing huge minions and then copying them!  Galvadon is just icing on the cake.