This list is white pretty much just because Boros Charm is a lot of damage for the mana. You can build this deck black, mainly for Bump in the Night but also for some potential draw or at a push some Kolghan's Command Value. You can also build it green for Atarka's Command should you wish or even several of these colours! Atarka's Command is just a hard to cast Skullcrack in this list for the most part as you have so few creatures you will be attacking with. This doesn't make it a bad splash however as lifegain is basically the only thing you care about at all. That is the strength of this deck, not caring much at all what your opponents are up to.
Eidolon of the Great Revel
Ankh of Mishra
Zo-Zu, the Punisher
The thing I like most about this sort of deck is how you can apply statistical analysis to it. Because it is so linear you can do far more relevant number crunching. You could run it through one of Frank Karsten's simulators and get fairly decent information on it. The assessment of cards comes down to how much damage they do to the face and for how much mana. There are only a couple of cards you ever play that give you interesting choices!
Exquisite Firecraft should probably just replace Zo-Zu, if Ankh is bad on the draw.... Uncounterable is pretty nice in this deck and four is a nice big chunk. There are lots of ways to fine tune this deck, some give you better draws, some give you better uses for excess mana, some are better against creatures but all told the decks are very very similar. The deck isn't done very often, mostly because it isn't that fun or interactive while RDW is should you want to sling fire and lightning about the place. Also, to tune it at all or do exactly what you want you have to look outside of the main drafting cube. Ball Lightning is a bit narrow these days to be a maincube card, Pyrostatic Pillar the same. Then you have things like Lava Spike which is one of the best cards in the deck but has no place in any list bar this.
Volcanic Fallout is a card you don't see in any RDW lists however in this deck it is well worth it. Against something like a white weenie deck you can lose race and will be inclined to aim some burn at early dorks to give you the time you need. The trouble with this however is that you can wind up without enough burn to actually close the game. Fallout does kill basically all your stuff but you don't have much of it and it isn't all that hard to plan around it a bit. It is two damage to face so never dead and reliably wreaks any aggressive weenie strategies.
This deck can win on turn 3 just through burn (4x one mana 3 damage spells, Fireblast and a 2 mana 4 damage spell with 3 lands) however this is super unlikely, the deck is much more likely to win around turn five with a good draw and not having to aim burn at dorks or otherwise being disrupted. It is not the speed of the deck that makes it daunting, it is a terminator like relentless that makes the inevitability of RDW look quite limp. The deck is so redundant that you pretty much can say every card is 2 and a bit damage (including the lands, the non-land cards average more like 3 damage). I some how manage to have talked quite a lot about a deck which has really very little to say about it so I guess I should wrap it up here....