Burn, good ol' burn. And old is exactly correct. Lightning Bolt has been around since the very beginning of Magic, and even Goblin Grenade is 17 years old. Michael Diezel has finished at least one of his matches telling his opponent: "See, this card is actually older than you are." Of course, he's using the Fallen Empires version.
His deck is a little different than most Goblin lists. "I don't have Goblin Chieftain and Goblin Wardriver. Those are only good if you're attacking with lots of creatures and especially after sideboarding that doesn't happen very often."
On the other hand, you do need Goblins to sacrifice to Goblin Grenade. "I'm using all the Goblins which are good on their own, like Spikeshot Elder, Goblin Guide, Ember Hauler, and Goblin Fireslinger," Diezel said. "But sixteen are not quite enough to reliably cast the Grenade. That's the reason for the two Goblin Bushwhackers."