This is the deck I used this month to climb through Diamond (after trying various First Flame decks in Gold), with a record of 28-11. (Edit: I stopped keeping track of record, but I reached rank 1 with this list on July 14.)
The idea of the deck is that it combines the best tribute enabler (7 copies of Combustion Cell counting the market) with the best tribute payoffs (Kenna and End of Hostilities). The rest of the deck is card draw, grenadins for Cell, and some cheap removal.
A few additional notes:
1) You want to redraw any hand that doesn't have Cell or Merchant. The deck is still functional without Cell (and has a bunch of card draw to go find it), but it's the most important card and always the first card you get with Merchant if you don't have one.
2) Hurler is usually the first card you feed to Merchant or Strategize, followed by excess Cells and snowballs or Granite Waystone-created grenadin. Gearcruncher is also a reasonable card to pitch early on if you have other high end, since it's usually the worst of your expensive cards.
3) End of Hostilities is amazing against basically any large unit that your opponent might play, but it's worth noting that it is especially good against Rizahn (since you can kill your opponent's Rizahn with your 2 copies immediately) and that it is great against Icaria, but you do need a snowball or Torch to break the aegis first. It's also incredibly disgusting on your own Kenna, since you get it right back along with another spell (and also make two 7/8 killers). Even just double copying an Ixtun Merchant can be a huge amount of value. One caution is that your opponent can respond to End of Hostilities with fast removal on the targeted unit, so you want to be aware of that.
4) Kenna is the best card in the deck - it is basically Carnosaur that draws you a Strategize or Wisdom (or End of Hostilities in longer games) and then threatens to do a lot of flying damage on the next turn, and you get to play it on turn 5 reasonably often with Cell.
5) The slots I'm most unsure about at the moment are the Jawbone Greatsword in the market and the 3rd Gearcruncher in the main deck. (Edit: now trying out extra Permafrosts and an Aeva in place of the maindeck Crunchers, and a Flamestoker in the market to make sure I have enough threats against control.)