Just because I decided to shake up the meta, here's the mono-red burn deck I built a few days ago on Magic: Duels. I call it Ping.(Yes, with the period.) I'm something like 25-4 with it already, and most of the losses were on dumb misplays from me. The games are quick and easy, it's brutally unfair and simplistic. I typically hover around rank 4 or so, because I'm usually playing with complicated decks, like my beloved 5 color planeswalker heavy mill deck. Obviously these decks lose a lot. I'm now at rank 13, the first time I've EVER cracked rank 10. All because of this deck. Some points about it:
1.) Most importantly: this deck only works as well as it does BECAUSE OF THE FORMAT. If everyone was running four of their bomb mythics, it becomes a lot less effective. It takes advantage of the one mythic restriction that duels imposes. Get rid of their best mythic card and you know you won't see it again all game(barring graveyard shenanigans). So in other words, I wouldn't try this deck in paper, or on Magic Online. It's great for duels, though.
2.) Cards and card quantity are all limited/shaped by what I have unlocked. Obviously you want a fourth furyblade, and a fourth fiery temper, I just don't have them yet.
3.) Wolf of Devil's Breach and Mirrorwing dragon are just in there because I was testing out finishers. They're basically unnecessary. Bedlam reveler seems amazing and is probably the only real finisher you need.(If you even need one at all)
4.) Baby chandra is just in there until I can replace her with either Oath of the Gatewatch or Kaladash Chandras. She sucks and is annoying.
5.) Wandering fumarole seems totally useless. Threw it in there thinking "late game blocker" if I got in trouble, but I've never once activated it, and there's no blue cards in the deck. Can easily drop for something else.
6.) Make mischief can probably be a better card, but it's not the worst possible option.
7.) Discarding a senseless rage to a furyblade vampire is a sick combo.
8.) Basically if your opening hand has at least two mountains, either/or thermo-alchemist/furyblade vampire and a spell or two, you'll cruise to a win. Mulligan'd all the way down to four one time to get a starting thermo and still won against an opponent who kept seven. The card puts in some serious work. One of each on the board at the same time is just filthy.
9.) The strategy should be straightforward. Ping away with thermo, cast a burn spell, ping again. Or discard madness cards to furyblade for max value, then swing in for a lot(or a little if she tramples). Usually the card you discard will burn out any blockers anyway. Save your instants until the combat phase to discard them to furyblade, if you have her down. Max value that way, and casts them for the madness cost instead.
10.) Collective defiance is an amazing burn card, and while you should wait until you can drop at least two of the three modes, don't be afraid to use it for just one mode if you have to. Remember: it's all ping damage once your thermo is down.
Enjoy and optimize to your tastes.