Mono red elemental deck. This is extremely fast and kills the opponent with things like Blistering Firecat and Ball Lightning. This deck functions like a very fast glass cannon, dealing as much damage as possible in the early turns using mana ramps and suicide cards. It's very common to swing for 6 to 7 damage on turn 3 and sometimes even 14 damage.
Putting Assault Strobe on one of the elemental can really put a dent in your opponents life total. Also, imprinting cards like Blistering Firecat under Mimic Vat makes it hard to lose. Three Demigod of Revenge are in to hold the deck up lategame. They are not only great attackers but also great blockers because of their flying and hold up very well against blue decks because they can't be countered (except if it's the first demigod played that game). The deck's only weaknesses are decks with lots of first strike or instant speed removal such as burn (I hate Lightning Bolt...).
A very nice synergy combo can be set up very easily with Flamekin Harbinger and Nova Chaser where Flamekin is championed under Nova Chaser. If Nova Chaser is killed, Flamekin returns to the battlefield, allowing you to search for an elemental card again. Assault Strobe on a Nova Chaser is also a one hit knockout.
A really nasty combo is having a creature out along with Flamekin Village or Mimic Vat and playing a Nova Chaser to get an easy 10/2 trample haste. Thanks to the mana ramp cards in this deck, it is possible to easily pull a combo off such as this on turn 3.
This is probably the 5th or 6th version of this deck. A lot of time playing MTGO has been put into making this deck what it is. On this current build, it easily wins consistently turn 4 or 5 with a good hand. If you have any ideas on how to improve this deck, please leave a suggestion. Constructive criticism is very welcome. Also, ideas for a sideboard are welcome. Thanks!
PS: This is a great deck to make if you want to get into legacy with a really low budget.
Update 5/3/16: I took out 2x Infernal Plunges, 1x Assault Strobe, and 1x Reforge the Soul.
I took eznogood@mtg's advice and put in 2x Sundial of the Infinites to hold the deck up mid and late game. Thanks, eznogood@mtg! I also put in 2x Lightning Bolt for some removal. Another 2x Bolts are in the sideboard which I finally got around to making. The sideboard includes 2x of Valakut, the Molten Pinnacle which was suggested by Cirrusdrake. Thanks!
Update 5/3/16:
I took out the Sundials because they didn't perform as good as one would initially think. In their place, I added one more mountain and one more Lightning Bolt.
I haven't been keeping up with standard lately so feel free to suggest any cards that came out since the Theros block that would work in this deck. Criticism and ideas welcome!