Hearthpwn

Climbing with a 65% win rate from rank 5 to 1 so far.  Can beat most meta decks (except odd paladin, pretty much an auto loss haha).

Against druid, put pressure from turn one.  If you can get lots of minion damage through, you should be able to burn them towards the end, especially if you Counterspell some armor spells. I've faced mostly druids on my climb and I beat them most of the time, although luck is still sometimes against you if you can't get an early Counterspell vs armor spells.

Even warlock is (mostly) a joke.  Try and get out Explosive Runes as early and often as possible so you can easily trade into giants, let them tire themselves out, and Fireball em to death.

Keep up tempo when against miracle rogues.  The secrets help.  Keep in mind they have no real way of healing themselves, so try to think a couple turns ahead when it comes to setting up lethal.

Recruit hunter requires a bit of luck. It's similar to the match against miracle rogues - just keep up early pressure and try to burn them down to 0 by turn 6-8.  The secret variant is harder than the Prince Keleseth variant.

TL;DR - apply early pressure with Mana Wyrm, Sorcerer's Apprentice, and secrets. Try to plan a couple turns ahead and set up for that lethal. If they still have coin, try to get out Explosive Runes first if you can to bait out the coin. Or if you have both Counterspells in hand, just set em up one at a time even if they do have the coin. It should still help keep tempo on your side.

Against Paladin, you could try to tech in one or two Arcane Explosions. Not really sure what to sub out, but keep in mind it would be a dead card everywhere else. Might be better to use Breath of Sindragosa.