Things went considerably better for me tonight. No stupid flood/mulligan problems, so yay.
So here is the more discard oriented aggro build I am screwing with.
Cryptbreaker x2
Dread Wanderer x2
Festering Mummy x3
Graf Harvest x1
Fatal Push x3
Binding Mummy x3
Miasmic Mummy x2
Wayward Servant x3
Scrapheap Scrounger x2
Smuggler's Copter x2
In Oketra's Name x2
Declaration in Stone x2
Plague Belcher x2
Lord of the Accursed x3
Alms of the Vein x3
Liliana, the Last Hope x1
Kalitas, Traitor of Ghet x1
Gisa's Bidding x2
Plains x5
Swamp x6
Shambling Vent x2
Isolated Chapel x2
Evolving Wilds x4
Cradle of the Accursed x2
Honestly not sure if
Miasmic Mummy is worth it over Key here, which is what was in their spot before. Key just hasn't really performed for me here like it has in my Rakdos/Dimir Madness decks.
The unblockable aspect really doesn't seem that great here. Outside of Plague Belcher (who has Menace) and maybe Kalitas we aren't likely to have any large single creatures to try and force through, and the prevalence of Menace and tap down effects can make sneaking damage in pretty easy without it. Most of my wins have come from either life drain, or huge alpha strikes.
On the aspect of activating madness, the best things it has going for it are that it is free (unlike Cryptbreaker and Miasmic) and that it can be activated at instant speed (unlike Miasmic, and to a lesser extent Copter).
As always Key can help with flooding, so I definitely consider that as well.
The biggest issue I had with Key here honestly? Most of our early turns we would rather be playing zombies to flood the table, or removal to push damage through. Most of the time we aren't going to want to be dropping it until relatively late in the game, at which point a lot of the time I would have just preferred it to be another threat.
Hence the testing with Miasmic. While he can't function at instant speed like Key can and costs a little more than Key to facilitate Madness he is another threat, which happens to be a zombie, and also forces your opponent to discard.
In testing it has been a little clunky, but some of the stuff has been pretty silly.
T1 Dread Wanderer, T2 Wayward Servant, T3 Miasmic+Alms isn't a bad start at all.
Cryptbreaker+Bidding is pretty silly when you drop three 2/2 tokens on the table at instant speed, especially if you already have one or multiple lords/servants/binding mummies on the table already. Miasmic Mummy can do the same thing at sorcery speed for the same cost, but he also get the added bonus of making your opponent discard a card.
I got lucky enough earlier to go T2 Servant, T3 Servant, T4 Binding Mummy, T5 Miasmic+Bidding....get three 2/2 tokens, do 6 damage, gain 6 life, tap three of the opponents creatures, make opponent discard a card....and SWING.