For many years, the defining characteristic of competitive Legacy decks was that they could beat a turn one Goblin Lackey. Cards like Lightning Bolt and Swords to Plowshares were absolutely mandatory, as were blockers like Wall of Blossoms. Since Deathrite Shaman has become prevalent, it's become harder and harder to actually connect with a Goblin Lackey, especially with Fatal Push entering the format as well. The format has changed, and Goblins has evolved with it. Let's take a look at what Goblins looks like in 2018:
Goblins - Legacy | Mediocre_Man, 5-0 Legacy League
- Creatures (28)
- 1 Goblin Settler
- 1 Goblin Sharpshooter
- 1 Krenko, Mob Boss
- 1 Siege-Gang Commander
- 1 Stingscourger
- 1 Tuktuk Scrapper
- 2 Gempalm Incinerator
- 4 Goblin Chieftain
- 4 Goblin Lackey
- 4 Goblin Matron
- 4 Goblin Ringleader
- 4 Warren Instigator
- Instants (6)
- 2 Pyrokinesis
- 4 Tarfire
- Artifacts (6)
- 2 Chrome Mox
- 4 Aether Vial
- Lands (20)
- 8 Mountain
- 4 Cavern of Souls
- 4 Rishadan Port
- 4 Wasteland
Efficiency is the name of the game. In previous years, Goblins was an overwhelming midrange deck. Control decks would fold to the endless chain of Goblin Matrons and Goblin Ringleaders. With cards like Snapcaster Mage and Jace, the Mind Sculptor giving control decks a means of keeping up with that card advantage engine and Deathrite Shaman and Fatal Push undercutting the power of Goblin Lackey, what's a Goblin mage to do?
The key to this deck is maximizing your chance to hit with either Warren Instigator or Goblin Lackey. Then, rather than worrying about grinding away with Ringleaders and Matrons, you're trying to just kill your opponent. You have Chrome Mox to help you cast Warren Instigator early, as well as Cavern of Souls to force your Lackey effect through counterspells. Tarfire and Gempalm Incinerator also help in forcing your creature through.
Once you get your first hit with a Goblin Lackey, the game fundamentally changes. You get to cheat in something like Goblin Ringleader or Goblin Matron for more removal, which helps you get additional triggers. Siege-Gang Commander lets you start going wide, especially when you follow up with Goblin Chieftain. Alternatively, you can go absolutely broken with Krenko, Mob Boss and a haste enabler.
Goblins may not be the dominant force in the metagame that it once was, but anyone who underestimates the Goblin engine is either going to get run over in the first few turns of the game or absolutely ground out in the late game. If your opponents aren't packing enough sweepers or Umezawa's Jittes, then maybe Goblins is a good call for your metagame.