Hearthpwn

Rank
In October 2018, I reached rank 3 playing this deck. After rank 3 I got caught up in work so I didn't have the time to push this deck even further.

The power
The deck relies on mechs and their synergies - Kangor's Engless Army is the true powerhouse of the deck. It usually revives 3 minions that are at least 10/10 in stats each. Another strength is your 7 mana 20/24 Lynessa Sunsorrow with Deathrattle: Summon two Stegodons

How to play
Try to be aggressive in the beginning of the game. Throw down your low costing minions and try to make them as stickey as you can by spending your buffing spells right. Always prioritize killing non-mechs over mechs, even if that means getting lesser value when trading. If you mindlessly run your 1/3 Glowtron, Kangor's Endless Army becomes weaker by the second. 

With the addition of Dinosize, you can often burst the opponent down as if pre-nerf Pyroblast.

Mulligan
Keeps: Glow-tron, Firefly, Keleseth, Blessing of Might (if paired with Glow-tron or Firefly)

If you see good curve (preferably magnetic), keep it as well.