Forbidden Alchemy isn't a horrible card, it's just that with DKA out, there are now better options. Mulch if you need some lands, Dream Twist is just a straight up mill for 3 for 1 mana, which is better than dumping two more mana to keep a card. Thought Scour is just powerful as it's a mill two, draw one for one blue mana. Faithless Looting is even more powerful than that for a red, and Shriekhorn just lets you mill for 6 for one measly mana.
Forbidden Alchemy just doesn't help as much for it's cost, and half the time you mill stuff, it'll either be creatures to build up power for your scary Splinterfrights, or spells you can flashback, like Tracker's Instincts or Gnaw to the Bone.
tl;dr Forbidden Alchemy is an inferior option to say, four Tracker's Instincts. And active tap or mana-costed mill effects on creatures are just not good for this kind of deck which really needs the mana early on to drop scary things like Boneyard Wurms, Screeching Skaabs, and Splinterfrights.
This might just be me being greedy and wanting to jam my foil Urborgs and Empty the Pits, but the power of instant-speed zombies is pretty high now, what with recent bannings about to shake the format hard. And how do we beat the timewarps deck? I can't seem to present a clock fast enough. A combination of graveyard hate in conjunction with a fast clock seems to be the right answer, even going so far as to up the RiP / Memoricide count a bit.
Rooftop Storm lets you cast your zombies for free.
Coat of Arms is disgustingly powerful and enables an alpha strike with even a small cadre of zombies.
Rite of Replication in conjunction with diregraf ghoul is a huge boost and can easily nuke someone out of orbit if someone wraths the board.
On the contrary, I really don't mind paying that small cost to remove your most dangerous thing to me. If I hit something like Spike Jester or Madcap Skills, it's 2 life to prevent 3 and upwards, which is solid.
Life is only a resource, after all, and what's the difference between winning with 1 or 10 life? Lately I've been liking deathrite in my sideboard anyways because junk reanimator cropped up like a fiend in my local meta, and I'd rather drop Deathrite turn 1 anyways.
My current list:
4 Witchstalker
4 Gladecover Scout
4 Boon Satyr
4 Eidolon of Countless Battles
4 Elvish Mystic
//Enchantments (12)
4 Ethereal Armor
4 Unflinching Courage
4 Madcap Skills
//Spells (6)
3 Boros Charm
2 Ajani, Caller of the Pride
1 Domri Rade
3 Temple Garden
4 Stomping Ground
4 Temple of Plenty
1 Temple of Abandon
3 Plains
3 Forest
4 Sacred Foundry
4 Hopeful Eidolon
2 Fiendslayer Paladin
1 Domri Rade
2 Armed // Dangerous
4 Selesnya Charm
2 Revoke Existence
Honestly, this list is pretty sweet, although a lot of numbers are currently tentative.
1 Azorius Chancery
1 Breeding Pool
1 Coastal Tower
1 Command Tower
1 Elfhame Palace
6 Forest
1 Glacial Fortress
1 Hallowed Fountain
6 Island
6 Plains
1 Savannah
1 Seaside Citadel
1 Selesnya Sanctuary
1 Simic Growth Chamber
1 Skyshroud Forest
1 Sunpetal Grove
1 Temple Garden
1 Temple of Mystery
1 Tropical Island
1 Tundra
1 Verdant Catacombs
//Creatures
1 Azami, Lady of Scrolls
1 Bloom Tender
1 Eternal Witness
1 Farhaven Elf
1 Fiend Hunter
1 Karmic Guide
1 Kazandu Tuskcaller
1 Leonin Relic-Warder
1 Mirror Entity
1 Mistmeadow Witch
1 Murkfiend Liege
1 Phyrexian Metamorph
1 Reveillark
1 Sakura-Tribe Elder
1 Skyward Eye Prophets
1 Solemn Simulacrum
1 Stonecloaker
1 Sun Titan
1 Venser, Shaper Savant
1 Wonder
1 Arcane Denial
1 Beast Within
1 Beck // Call
1 Blue Sun's Zenith
1 Capsize
1 Cultivate
1 Kodama's Reach
1 Pact of Negation
1 Regrowth
1 Rite of Replication
1 Rout
1 Skyshroud Claim
1 Spell Crumple
1 Swords to Plowshares
1 Time Stop
1 Time Warp
1 Voidslime
1 Walk the Aeons
1 Wrath of God
//Artifacts
1 Swiftfoot Boots
1 Sol Ring
1 Simic Signet
1 Azorius Keyrune
1 Selesnya Signet
1 Mana Vault
1 Gilded Lotus
1 Darksteel Ingot
1 Basalt Monolith
1 Crystal Shard
1 Ashnod's Altar
1 Bident of Thassa
1 Aura Shards
1 Collective Blessing
1 Doubling Season
1 Earthcraft
1 Freed from the Real
1 Helix Pinnacle
1 Mirari's Wake
1 Presence of Gond
1 Rhystic Study
1 Squirrel Nest
//Planeswalkers
1 Venser, the Sojourner
Combos ahoy:
Eternal Witness + Venser, the Sojourner/Crystal Shard + Time Warp/Walk the Aeons = infinite turns
Creature + Presence of Gond + Intruder Alarm = Infinite Elves
Derevi + Bloom Tender + Ashnod's Altar = infinite colorless mana
Bloom Tender + Freed from the Real + Blue permanent + any other color permanent = infinite colored mana that isn't blue
Earthcraft + Squirrel Nest = infinite squirrels
I've been riffing something not too dissimilar to this list though, seeing how Derevi easily could be a solid voltron commander since it's flashable.
21 Swamp
4 Mutavault
Creatures:
1 Veilborn Ghoul
Enchantmments:
1 Curse of Death's Hold
2 Dead Weight
1 Demonic Rising
2 Homicidal Seclusion
Instants/Sorceries
4 Sign in Blood
2 Corrupt
3 Doom Blade
2 Tribute to Hunger
4 Mutilate
2 Liliana of the Dark Realms
3 Liliana of the Veil
Artifacts:
3 Ratchet Bomb
4 Sign in Blood
1 Staff of Nin
4 Haunted Plate Mail
2 Appetite for Brains
1 Dead Weight
2 Devour Flesh
3 Duress
1 Homicidal Seclusion
2 Pithing Needle
1 Illness in the Ranks
2 Underworld Connections
1 Veilborn Ghoul
Shadowborn Demon: Seriously, he's a Shriekmaw on crack. Cast him, blow up something. There's less demons than black creatures in EDH.
Garruk, Caller of Beasts: It's +1 is Lead the Stampede, and you can slam dudes with his ability. A pinch pricey if budget concerns exist though.