Haven't seen a recent Rakdos Anvil writeup, despite the deck being great (I just hit Mythic with it, and fought at least a couple mirrors on the way).

My list:

Deck
4 Oni-Cult Anvil (NEO) 230
4 Shambling Ghast (AFR) 119
4 Deadly Dispute (AFR) 94
4 Experimental Synthesizer (NEO) 138
4 Voldaren Epicure (VOW) 182
4 Bloodtithe Harvester (VOW) 232
4 The Meathook Massacre (MID) 112
1 Agadeem's Awakening (ZNR) 90
4 Blightstep Pathway (KHM) 252
2 Den of the Bugbear (AFR) 254
4 Mountain (NEO) 290
7 Swamp (NEO) 288
4 Haunted Ridge (MID) 263
2 Shatterskull Smashing (ZNR) 161
2 Lolth, Spider Queen (AFR) 112
2 Immersturm Predator (KHM) 214
3 Voltage Surge (NEO) 171
1 Anje, Maid of Dishonor (VOW) 231

Sideboard
2 Abrade (VOW) 139
4 Duress (STA) 29
1 Feed the Swarm (ZNR) 102
2 Soul Shatter (ZNR) 127
2 Feed the Swarm (ZNR) 102
2 Go Blank (STX) 72
1 Voltage Surge (NEO) 171
1 Sorin the Mirthless (VOW) 131

The core of the deck is 4x Voldaren Epicure, 4x Oni-Cult Anvil, 4x Meathook Massacre, 4x Deadly Dispute, 4x Experimental Synthesizer, and 3-4x Voltage Surge. I wouldn't consider any build that didn't include those core cards.

Shambling Ghast and Bloodtithe Harvester are quite strong as well. I've been running them currently as they synergize well with Immersturm Predator and Anje, but I also tend to side them out in some matchups. With different late-game bombs, I'd consider thinning/removing these cards.

Immersturm Predator, Lolth, and Anje were later additions; I had started out with a very low-to-the-ground approach with no cards above ~2mv, and quickly found myself wanting more powerful mid-late game cards. I'm not certain I've found the optimum numbers for these cards yet. Anje is incredibly strong if you can untap with her; she can often eke out an 8-12 point life swing without too much fuss. I'm also considering space maindeck for 1-2 Sorin the Mirthless, because this deck loves extra cards and extra tokens.

The worst matchups are (a) against other Meathook Massacre decks, especially since Orzhov has better enchantment removal than Rakdos does, and (b) the Goldspan/Lier combo decks. Feed the Swarm in the board helps with the first matchup, and Go Blank with the second.

Edit: Just got wrecked in a mirror match by a list running [[Sozenkan Smelter]] and [[Moonveil Regent]], both of which push the deck into more aggressive territory.