From the Wizards of the Coast website:
Fifth Dawn Theme Deck
One of the highlights of the Fifth Dawn set is the new sunburst mechanic. Artifacts with sunburst reward decks that play many colors of mana, and the "Sunburst" deck is set up to take full advantage. If you spend four or five different colors of mana on a card like Skyreach Manta, the results can be devastating. With a little luck and a Sylvok Explorer, you could have that 5/5 flier in play as early as turn four!
The key to winning with this deck is getting access to as many colors of mana as you can as quickly as possible to maximize the power of your sunburst cards. Darksteel Ingot, Pentad Prism, and Dawn's Reflection help your mana so that you don't even need to depend on drawing the right lands to power up your sunburst spells. An early Chromatic Sphere often nets you a card and an extra counter on one of your permanents.
The most important noncreature cards in the "Sunburst" deck are Energy Chamber and Infused Arrows. With an Energy Chamber in play, you can add a charge counter to your Pentad Prism to get more mana or just put another +1/+1 counter on an artifact creature to speed up the assault. Infused Arrows deals with your opponents' small attackers and gets rid of creatures with annoying abilities. It's also particularly nasty when combined with Energy Chamber.
In a deck designed to maximize the effect of sunburst cards, Etched Oracle is a 4/4 creature for four mana most of the time, which is impressive by any standard. Even if your opponent manages to deal with the Oracle, you can respond by using its ability to draw three cards. That's not a bad trade! Suncrusher and Sawtooth Thresher have abilities that make good use of their extra counters.
Play with the deck for a little while until you get a feel for how the mana is set up. Keep in mind that you want to have access to all five colors of mana by the fifth turn (or earlier). You can replace the basic lands with lands that produce multiple colors of mana or add a few Talismans from the Mirrodin set. After you see how much fun Energy Chamber is in the deck, you'll probably want to add more of these as well. Overall the deck is a blast to play—turn-four 5/5 fliers and unlimited charge counters are always fun!
Cards in this deck: