Engineered Explosives, one of the Fifth Dawn preview cards with the new Sunburst mechanic, is an example of how an artist can visually explain a card's purpose. There are two clues in this picture that relate to how the card works.
First, the Sunburst mechanic says, "This card comes into play with a charge counter on it for each color of mana used to pay its cost". In the Fifth Dawn story, the five suns are used to represent the five colors, and thus appear in the background of the art (and if you look closely as you open up open your Fifth Dawn boosters, you'll see this theme repeated)
Second, Engineered Explosives allows you to destroy each nonland permanent with converted mana cost equal to the number of charge counters on Engineered Explosives. To represent this, Ron Spears shows two Loxodons bursting into flames while a Soldier stands between unscathed. While you could debate which Loxodon's are exploding, my bet is that they are Loxodon Mystics since their casting cost of fits perfect with a WUBRG deck.
For more information on Engineered Explosives read "A Dirtier Deed?" by Anthony Alongi.
Engineered Explosives by Ron Spears