After a long absence from Legacy I jumped back in this past weekend playing LED Dredge, my old favorite. I ran it without Dread Returns in a play on the old fashion, adding a playset of Street Wraith as is the new fashion.
What I ran:
4x Bridge From Below
4x Narcomoeba
4x Cabal Therapy
3x Ichorid
4x Golgari Grave-Troll
4x Stinkweed Imp
3x Golgari Thug
4x Faithless Looting
4x Breakthrough
3x Careful Study
4x Street Wraith
4x Lion's Eye Diamond
2x Putrid Imp
4x City of Brass
4x Gemstone Mine
2x Mana Confluence
3x Cephalid Coliseum
I think I made a few sub-par plays, but three games had really explosive starts that were starved by failing to chain dredgers, or basically a turn wasted using a draw spell just to discard dredgers resulting in a slow start.
On the drive back I was pretty intrigued by a decklist that 5-0'd a Legacy League that looked like this.
4x Bridge From Below
4x Narcomoeba
4x Cabal Therapy
4x Ichorid
4x Nether Shadow
4x Golgari Grave-Troll
4x Stinkweed Imp
4x Golgari Thug
4x Faithless Looting
4x Breakthrough
4x Street Wraith
4x Lion's Eye Diamond
4x City of Brass
4x Gemstone Mine
2x Mana Confluence
2x Cephalid Coliseum
This build is basically T1 combo into full g/y based aggro, cutting all Careful Studys and Putrid Imps for Nether Shadow and upped dredger and Ichorid counts, and also cutting another land. I've been testing pretty heavily and I'm really enjoying the build, which consistently gets out several creatures T2 for quick beats.
Street Wraith shenanigans are pretty fun too
>Cycle SW, sack LED in response
>Cast Draw Spell, Cycle SW, sack LED
etc.
Nether Shadow/Ichorid sometimes trip over each other though, as the black creature card you exile with Ichorid then can't be used towards the Nether Shadow trigger upon resolution.