Kiln fiend decks are fast combo decks with consistent T3 T4 kills. The basic premise is to play spells in order to pump your beater, give it unblockable, give it double strike, and swing for at least 20-26 damage.
As for the individual card choices:
-I use peek over probe due to instant speed, but either choice is viable
-I run 4 temur battle rages in addition to the normal assault strobes because of the added trample and having both in the deck makes everything run much more consistently.
-Beyond playsets of the Kiln Fiend and Nivix Cyclops I also run one copy of Shu Yun and Flamekin Harbinger.
-Shu Yun, while not as explosive as fiend or cyclops can still beat down effectively. He also acts as a source of double strike on a stick. He is mostly included in order to increase the low creature count.
-Flamekin Harbinger acts as a tutor for kiln fiend (or nivmagus elemental if post-board in certain matchups). This card is also useful in GBx match ups against liliana.
-Young Pyromancer acts as a means of stalling your opponent until you can reassemble your combo after significant disruption or can even win you the game in some cases. Also, he is great against GBx decks that run liliana.
-Crimson Wisps is necessary against decks running playsets of liliana (chainer's edict on a stick is very annoying. The card discard is somewhat irrelevant). With wisps it is possible to assemble the combo in your hand and burst your opponent down in a single turn when a game runs longer than you would like.
-Stubborn Denial acts as a negate for U as long as any one of the nine beaters is in play.
-Nivmagus Elemental is great against blue control decks such as twin [WHILE TWIN IS GONE, THIS CARD STILL EXCELS AGAINST TEMPO/ CONTROL STRATEGIES]. Not quite as explosive as fiend or cyclops, but is cheaper and can be even more sturdy.
-Rending Volley is mostly here for twin, but is also useful against other annoying decks such as Death and Taxes. [WITH THE BANNING OF TWIN, THIS CARD WILL MOST LIKELY BE REPLACED, BUT I'M NOT SURE BY WHAT YET, MAYBE TWISTED IMAGE...]
-Smelt is mostly included for spellskite. There are other cards that are even better at dealing with spellskite (eg, twisted image), but I still stick with smelt since it has more applications.
-As for the manabase everything comes into play untapped for obvious reasons (tapped lands are just too slow). I currently only own two Steam Vents, but I plan on purchasing heavily played/ damaged versions soon.
