Encounter 2 of the Essentials Red Box adventure features 8 Kobold Tunnelers and a Fledgling White Dragon, a level 1 solo. As far as I know, Fledgling is a new category: Draconomicon introduces Wyrmlings, which are low-level Elites, but this Fledgling is a solo dragon.
I know this is an unpopular viewpoint, but I’m not a huge fan of killing babies. I don’t feel like a Real Man killing a dragon until it is at least an adult. Still, kudos to WOTC for managing to pack a dragon into the Dungeons and Dragons starter set. It’s in the name. It’s on the cover art. It’s nice to have one in the Red Box.
Dragons weren’t in the Mentzer Red Box solo adventure, but they were in the bestiary, and they were TOUGH. Too tough, I’m sure, for a level-3 party.
This encounter, too, is billed as a difficult one: “By itself, without any help from the kobolds, the dragon would be a tough opponent. […] If there’s any question, feel free to tell the players that their characters should be afraid of this deadly creature.” If the PCs are smart, they’ll talk to the dragon; that will lead to a skill challenge on the next page. Hopefully they’re not smart, because then they’ll get to FIGHT A DRAGON. Badass. If they win, they’ll pick up some money and a set of +1 darkleaf leather armor.
The white dragon fledgling looks like a pretty standard white dragon, except that it has a cool ability, Savage Blood: “While the dragon is bloodied, it scores a critical hit on a roll of 17-20.” The kobold tunnelers are standard kobold minions, with an immediate interrupt that gives them a saving throw to avoid close and area attacks.
On, by the way: best detail that will never make its way into actual play: “Each altar has two magical candles burning atop it, despite the kobolds’ continual efforts to extinguish them.” Hijinx!