So since the Standard meta has turned out to be unplayable garbage that varies between decks that win by not letting you play the game and decks that are 100% randomly generated I decided I might as well pass the time by farming all of the experience-granting achievements, most of which I've completed by now (which wasn't fun).
As a result, I think I can offer some valuable tips for those who haven't quite gotten around to them yet (especially since we don't have a dedicated thread for it yet).
Basically I'm just gonna go through every achievement and offer some general pointers on how to get them done the most efficient way.
As always, let me know if you have better ideas.
Demon Hunter
VENGEANCE...Next turn: Incredibly obnoxious but simple. Activating 200 Sigils isn't easy on account of there only being 2, which means you can trigger 4 per game at max (and you might not even get that depending on who you're facing). I recommend combining this with other achievements because it will take a while (50 games at least). You can also try finding extra copies through Venomous Scorpid.
Don't Dead Open Inside: Wild is your best friend if you have [Hearthstone Card (N'zoth the Corruptor) Not Found]. If not, Khartut Defender still does a great job at speeding up the process. Death Speaker Blackthorn helps, but is far from necessary. Teron Gorefiend can also put in work if you have him.
To the Left-Mooost! To the Waaall!: Easy if you have Kurtrus Ashfallen. If not, you can try and get him off Illidari Studies (which is what I did, although I wouldn't recommend it).
Druid
The Final Frontier: Seems really hard to achieve without Aviana and Kun the Forgotten King. Ysiel Windsinger might also do the trick with enough set up (and preferably in Wild because Ultimate Infestation). Completing this the intended way through Celestial Alignment sounds like a bad joke. Getting Alignment off and ramping back to 5-mana with five 8+mana cards is a pipe dream. If you didn't get run down by that point your opponent will usually concede anyways.
EDIT: Apparently Aviana + Kun doesn't work for some reason, so Alignment only it is (or maybe Ysiel, but I don't think anyone even owns that card).
Buy One, Get One Free (of Taunt): Possibly the most obnoxious one. The best way to do this is by going into Wild, building a full cycle/ramp deck and then combining Plaguemaw the Rotting with Animated Broomstick and up to 5 small taunts such as Frostwolf Grunt, Goldshire Footman, Tournament Attendee and of course Thorngrowth Sentries. Getting more than one round of resurrects is very optimistic because the average player is a <snip snap> who can't possibly comprehend the concept of farming for achievements and will literally dump their entire hand just to get rid of Plaguemaw even if you haven't made any effort to actuallly win the game for 5 turns. At least you only need 50 procs total.
Do it for the Vines: Go wild, stock up on cycle and ramp and just go to town. Usually, 3 combos per game should be definitely possible.
Hunter
Who Let the Dogs Out?: As easy as it gets apart from the fact that Hunter is hot garbage at the moment. Wild will probably be a better plays, simply because it has more Beasts with Rush that you can use (mainly Diving Gryphon and Hench-Clan Hogsteed).
Like Raptor, Like Son: Thanks to the unnerfed Starving Buzzard, this one is quite easy as long as you also run Pen Flinger with small spells and queue into a control deck. Tol'vir Warden also helps a lot if you have it.
Pack Attack: Same principles as the previous one, except you run even more cheap spells. Notice that you don't have to actually fill the board, just summon at least 6 (which you can trade off at any point) so playing double Pack Runner helps, even though a single one shouuld be enough.
Mage
It's not "Spamming", It's Art: Play Hero Power Mage. A lot. It's not good, but there's worse things.
Shatter Combo: Put a strong focus on Freeze spells into any Mage deck and go to town. Wild probably makes it a lot easier, but it's not necessary.
Barrens Bubbler: Just play Spell Mage without Deck of Lunacy and eventually you'll get there.
Paladin
Wear Your Sunday Best: 28 Minions, 2 copies of Invigorating Sermon. Also Knight of Anointment. Surprisingly enough, the deck isn't nearly as bad as you would expect if you put in enough good rush and Divine Shield cards.
Spell Slingin' Savior: Wild is mandatory here because of how much draw options there are for Paladin there. If you don't have your Flash of Light or Crystology still around you will be very sad. The best way is to run Libram of Wisdom and Lady Liadrin and focussing on getting back a lot of those. Then hope you're playing against a control deck and keep making Recruits that you stack with 5 Librams until you die.
Just between You and Me: Wild is equally mandatory here. Standard secrets are onlny 5 in number and at least two of them are quite hard to proc consistently. The best combo includes Noble Sacrifice, Avenge, Getaway Kodo and Redemption. The fifth secret is flexible and will probably vary in efficiency between match-ups. [Hearthstone Card (Oh my Yogg) Not Found] or Never Surrender! are probably the best options.
My recommended strategy is to collect secrets (and keep a Sword of the Fallen online to fish the last secret) and then play at least one Secretkeeper alongside another minion, which should present enough of a pile of stats for your opponent to respond immediately and hopefully being forced to trigger all the Secrets in one turn.
Priest
Blood Donation: Play Serena with Broom. As easy as it gets.
Two Health Bars: Go into Wild, pack all the healing spells you can find as well as a decent control package and hope you queue into something that's not an OTK deck. It's not hard, healing your opponent is not necessary, but can help.
Why Can't I Hold All These Cards?: Galakrond Priest in Wild. JUst run most of the Galakrond stuff to keep hand size consistent as well as some amount of draw. Then just play the control game as efficiently as possible while maintaining 9 cards in hand (you don't have to mill cards to get the achievement).
Rogue
Identity Theft is not a joke: Either have Yoink! or find ways to discover it (Wandmaker, Scorpid, etc.)
Just Don't Touch the Blade: The new Field Contact Miracle Rogue is a great deck for all of these achievements. You can cycle through the deck rather qquickly and find what you need. IN order to minimize Ooze depression I recommend doing it all in a single turn.
Magnets, How Do They Work?: Galakrond Rogue in Wild. Umbral Skulker and the big G himself make this a walk in the park. Other than that, Efficient Octo-bot will probably also do the trick, but you won't be able to fight for the board as much.
Shaman
My Dear Watson: Wild has more Elementals, but Standard works too. 30 Elementals or no balls.
Murlockdown: Murloc Shaman sucks dick in Standard, but it suffices. Ideally you go into Wild and use all the actually good Murlocs to get it done.
Extra Organic: Spell Damage Shaman ftw. Bru'kan probably makes this super easy, but you can do without him. Wild is probably a better avenue because Shaman has more draw there.
Warlock
Shadow of a Shadow: Obviously Tamsin Roame is the main card for this. If you don't have her you can try using Emperor Thaurissan with cheap spells in Wild, but that will take a while and is probably not worth the time.
What's Better than Two Imps?: Neeru Fireblade is how you're supposed to complete this. Don't do that, you'll probably die before you get to play him. Instead, just type "Imp" into the search bar, go into Wild and build a deck full of Imp cards. It'll take a while, but you'll get there eventually.
Discard Inferno: If you are a poor peasant you'll have to use Envoy Rustwix with an empty deck. If you are a galaxy-brained elite like me, you just build a 29 legendary deck with one Altar of Fire in Wild and tap until you find it. Easiest achievement ever.
Warrior
Hardcor Rancor: Mad Summoner is your best friend. All you need is an empty board on your side and at least one empty space on the enemy's.
It'll Take More than That: Apparently this is bugged and works for every class. As such it essentially auto-completes as long as you play minion-based deck. If they fixed it by now you can just play Frenzy Warrior which goes great with one of the neutral achievements.
Gym Buddies: The wording here seems confusing, but all you need is two of the same minion in hand and both copies of Bulk Up. Just build for draw and it'll happen. Just make sure not to run any other Taunt minions.
Neutral
Sting Operation: Since a few of the above achievements require certain spells or running only minions you can jsut throw the Scorpid in and do it on the way. If you want to target it specifically you'll want Animated Broomstick or Warsong Commander.
Signature Moves: Obnoxious as fuck. Just throw Ranked Spells into every other Achievement deck that usually goes to 10-mana and play them along the way. As per usual, Spell generation can get you extra copies.
Frenzy Friends: Warrior is the best class for this, but you can do it any way you like. There's probably not even a reason to force this because it will complete by itself aas long as you play any deck with Frenzy minions in it.
Grand Guardian: Hunter or Druid. It's very simple. Primordial Protector you can get for free from the Tavern Pass so no need to craft it.
Maximum Security: If you're still playing Standard right now you've probably already completed this.
Life is a Highway: Fuck this entire thing. All the Caravans need to be buffed to 1/4s, it's actually absurd how bad they are other wise. Anyways, Paladin is the best choice for this because you have Righteous Protector, many buffs and more importantly, Gift of Luminance. Wild gives you the best draw options. You can also run Pursuit of Justice for fun. Rally! helps a lot with this as well.
I'm not gonna sugarcoat it, this one is pretty painful, mainly because the braindead playerbase will once again abandon all reason and attempt to murder your caravan with everything they have in their hand, so make sure you give them the maximum protection.
Everyone's in Here!: I thought this one was going to be hard until I realized....Commanding Shout + Bladestorm on an empty board (that you easily set up through Brawl into double Doomsayer) completes it easily. Also good for Frenzy farming.
Equivalent Exchange: Play a deck with good draw, run a couple of 10-drops and have a way to tutor your 0-mana 1/1 of choice (I prefer Crystology).
Build-a-Rock Workshop: Rogue is the most obvious choice because of Shadowstep. MAke sure you write down all your previous combinations so you don't forget which one's you're still missing.
Spawn Shop: Sounds annoying, but is actually pretty simple in Wild with hunter and all the Deathrattle synergies they have available. Play Dead, Nine Lives, Baron Rivendare, Necromechanic. The posibilities are endless. Draw is a bit of an issue, but the usual Tracking + Mad Scientist builds do the trick. Honestly, your biggest worry shouuld be winning too hard because it turns out spawning multiple big taunts over and over tends to grind down a lot of decks. Appease your opponent by refraining from caving their skull in so they tolerate your spawning shenanigans.
Hog Wild: Rogue. Wild. Brann Bronzebeard. Zola the Gorgon. Shadowstep. There is no better way. Efficient Octo-bot is great for setting up the combo.
Has Anyone Seen Mankrik's Wife?: First of all, you need to kill with the initial summon. Using the Mankrik minion after it has attacked won't complete the achievement.
Once again, Rogue in Wild is our saviour. Cycle through the deck quickly, throw burn into the opponent's face and then use Brann Bronzebeard, Mankrik and Shadowstep to finish them off. Just make sure you have enough space on the board for all the Mankriks.
Top Secret Snoop: As of now I consider this one uncompleteable by any normals means. There is no deck in Standard that currently runs 5 different Secrets (and plays them all that once). the only option would be Secret Rogue, which sucks balls, so you won't find it on ladder.
In Wild the situation isn't much better, mainly because the best Secret deck is Mage and I don't think you'll be able to survive without triggering their secrets.
If you desperately want this I'd just recommend throwing Operative into every deck you have and hoping to get lucky (in Wild). In Standard I wouldn't even bother because the only relevant Secret deck is Paladin and they only run 4 different Secrets.
Anyways, that's all I've got. I hope at least some of you found this helpful. If anyone got any more useful "cheats", feel free to post them.
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mod edit: removed excessive profanity (sinti)
