Red looks to be the most promising here due to the plethora of removal and reasonable selection of playable creatures. Some more 3 or 4 drops will be needed, however. Blue and black are the colors that will fit the bill, but Blue's Eler Deep-Fiend and Welcome to the Fold together have more power than the Bloodhall Priest. I would not play Geier Reach Sanitarium to enable madness, as it will benefit your opponent as well. I will however, incorporate a splash for the Bloodhall priest, since the manabase can afford it and we have fixers.
1) Your black isn't that strong. You're really just playing black to get Bloodhall and to have more creatures with type Vampire
2) RB has some Madness and Hellbent payoff in your pool, but you lack madness enablers (Insolent Neonate and your symmetrical land -- that's it!). Not enough enablers to make the synergy work.
3) You're running a lot of "pump spells" that are effectively card disadvantage. A few combat tricks are good for aggro, but you have 3 instant pumps, 2 auras and 1 equipment. That's too much. Those cards don't do anything if you don't have a creature on the board. Also, they can open you up to 2-for-1s or tempo loss.
Basically, I can see why that deck would struggle. There's better stuff in your pool.
Those blue Emerge guys are really good. You've got some good blue spells too. It's too bad you don't have many creatures that like to be sacrificed, because otherwise you could make a dangerous dedicated Emerge deck. Still, you can run some of them in UR.
I'd run basically the same deck as above, but I wouldn't bother to splash black for Bloodhall. This comes down to personal preference. You have the color fixing to make a splash work, but I think you lack the repeatable discard outlets (e.g. Ravenous Bloodseeker) to make Madness or an empty hand really happen. Also, blue decks don't want to empty their hands (even if it's just sandbagging lands to bluff tricks), which would make Bloodhall much weaker, though that comes down to personal playstyle. If you will empty your hand often, splash for Bloodhall. I like keeping tricks up.
Curve:
1 - ss
2 - cccss
3 - ccccccss
4 - ccs
5 - c
6+- eees
Brazen Wolves is amazing, but there are already so many 3 drops competing for space:
-Skaab is a top-quality 3-drop, especially with all the instants
-Uninvited Geist has evasion, and there are tempo tricks to force it through once
-Cultist is the ideal Emerge fodder
-Angler is reasonable to transform with 4 colorless creatures in the deck
-Scarecrow isn't needed for color fixing, but Horned Turtle seems good in this format, it helps Delirium, and it's a self-sacrificing colorless creature for Angler
-Stitched Mangler is questionable. Brazen Wolves is a better card overall, but this deck doesn't feel that aggressive and I think it would prefer a tempo trick like Mangler over an aggressive beater like Wolves
Up for debate. Anyway, this is a rough idea of what you could build. Seems better than RB.
1 Abundant Maw
1 Drownyard Behemoth
1 Elder Deep-Fiend
1 It of the Horrid Swarm
1 Wretched Gryff
White
1 Apothecary Geist
1 Collective Effort
2 Geist of the Lonely Vigil
2 Ironwright's Cleansing
1 Militant Inquisitor
1 Sigardian Priest
1 Steadfast Cathar
1 Thraben Inspector
1 Thraben Standard Bearer
1 Topplegeist
Blue
1 Convolute
1 Drag Under
1 Erdwal Illuminator
1 Exultant Cultist
1 Ghostly Wings
1 Grizzled Angler
1 Ingenious Skaab
1 Lunar Force
1 Pieces of the Puzzle
1 Silburlind Snapper
2 Spontaneous Mutation
1 Stitched Mangler
2 Trail of Evidence
1 Uninvited Geist
1 Unsubstantiate
1 Welcome to the Fold
1 Certain Death
1 Crow of Dark Tidings
2 Grotesque Mutation
1 Hound of the Farbogs
1 Markov Crusader
1 Midnight Scavengers
1 Strange Augmentation
1 Succumb to Temptation
1 Vampire Noble
2 Wailing Ghoul
1 Weirded Vampire
Red
1 Borrowed Hostility
1 Brazen Wolves
1 Deranged Whelp
1 Falkenrath Reaver
2 Galvanic Bombardment
1 Harmless Offering
1 Howlpack Wolf
1 Gatstaf Arsonists
1 Impetuous Devils
1 Insolent Neonate
1 Scourge Wolf
1 Senseless Rage
1 Spreading Flames
1 Stensia Banquet
1 Backwoods Survivalists
1 Crossroads Consecrator
1 Obsessive Skinner
1 Somberwald Stag
1 Springsage Ritual
1 Stoic Builder
1 Swift Spinner
1 Ulvenwald Captive
1 Watcher in the Web
1 Waxing Moon
2 Woodland Patrol
Multicolored
1 Bloodhall Priest
1 Campaign of Vengeance
1 Mercurial Geists
1 Mournwillow
1 Cathar's Shield
1 Cryptolith Fragment
1 Lupine Prototype
1 Wicker Witch
1 Wild-Field Scarecrow
Land
1 Geier Reach Sanitarium
1 Markov Crusader
1 Vampire Noble
1 Weirded Vampire
1 Brazen Wolves
1 Deranged Whelp
1 Falkenrath Reaver
1 Howlpack Wolf
1 Gatstaf Arsonists
1 Impetuous Devils
1 Insolent Neonate
1 Scourge Wolf
1 Bloodhall Priest
1 Certain Death
2 Grotesque Mutation
1 Strange Augmentation
1 Borrowed Hostility
2 Galvanic Bombardment
1 Senseless Rage
1 Spreading Flames
1 Stensia Banquet
1 Cathar's Shield
Lands
1 Geier Reach Sanitarium
6 Swamp
10 Mountain
Red looks to be the most promising here due to the plethora of removal and reasonable selection of playable creatures. Some more 3 or 4 drops will be needed, however. Blue and black are the colors that will fit the bill, but Blue's Eler Deep-Fiend and Welcome to the Fold together have more power than the Bloodhall Priest. I would not play Geier Reach Sanitarium to enable madness, as it will benefit your opponent as well. I will however, incorporate a splash for the Bloodhall priest, since the manabase can afford it and we have fixers.
My deck from this pool:
1 Erdwal Illuminator
1 Deranged Whelp
1 Falkenrath Reaver
1 Scourge Wolf
1 Wild-Field Scarecrow
1 Howlpack Wolf
1 Uninvited Geist
1 Ingenious Skaab
1 Stitched Mangler
1 Impetuous Devils
1 Mercurial Geists
1 Bloodhall Priest
1 Wretched Gryff
1 Elder Deep-Fiend
1 Gatstaf Arsonists
1 Welcome to the Fold
1 Unsubstantiate
1 Cryptolith Fragment
1 Ghostly Wings
2 Galvanic Bombardment
1 Spreading Flames
1 Borrowed Hostility
Lands:
9 Mountain
7 Island
1 Swamp
1) Your black isn't that strong. You're really just playing black to get Bloodhall and to have more creatures with type Vampire
2) RB has some Madness and Hellbent payoff in your pool, but you lack madness enablers (Insolent Neonate and your symmetrical land -- that's it!). Not enough enablers to make the synergy work.
3) You're running a lot of "pump spells" that are effectively card disadvantage. A few combat tricks are good for aggro, but you have 3 instant pumps, 2 auras and 1 equipment. That's too much. Those cards don't do anything if you don't have a creature on the board. Also, they can open you up to 2-for-1s or tempo loss.
Basically, I can see why that deck would struggle. There's better stuff in your pool.
Those blue Emerge guys are really good. You've got some good blue spells too. It's too bad you don't have many creatures that like to be sacrificed, because otherwise you could make a dangerous dedicated Emerge deck. Still, you can run some of them in UR.
I'd run basically the same deck as above, but I wouldn't bother to splash black for Bloodhall. This comes down to personal preference. You have the color fixing to make a splash work, but I think you lack the repeatable discard outlets (e.g. Ravenous Bloodseeker) to make Madness or an empty hand really happen. Also, blue decks don't want to empty their hands (even if it's just sandbagging lands to bluff tricks), which would make Bloodhall much weaker, though that comes down to personal playstyle. If you will empty your hand often, splash for Bloodhall. I like keeping tricks up.
1 Falkenrath Reaver
1 Deranged Whelp
1 Scourge Wolf
1 Stitched Mangler
1 Ingenious Skaab
1 Uninvited Geist
1 Exultant Cultist
1 Grizzled Angler
1 Wild-field Scarecrow
1 Mercurial Geists
1 Impetuous Devils
1 Gatstaf Arsonists
1 Wretched Gryff
1 Elder Deep-Fiend
1 Drownyard Behemoth
2 Galvanic Bombardment
1 Unsubstantiate
1 Ghostly Wings
1 Drag Under
1 Convolute
1 Welcome to the Fold
1 Spreading Flames
//Lands:
9 Mountain
8 Island
1 Brazen Wolves
Curve:
1 - ss
2 - cccss
3 - ccccccss
4 - ccs
5 - c
6+- eees
Brazen Wolves is amazing, but there are already so many 3 drops competing for space:
-Skaab is a top-quality 3-drop, especially with all the instants
-Uninvited Geist has evasion, and there are tempo tricks to force it through once
-Cultist is the ideal Emerge fodder
-Angler is reasonable to transform with 4 colorless creatures in the deck
-Scarecrow isn't needed for color fixing, but Horned Turtle seems good in this format, it helps Delirium, and it's a self-sacrificing colorless creature for Angler
-Stitched Mangler is questionable. Brazen Wolves is a better card overall, but this deck doesn't feel that aggressive and I think it would prefer a tempo trick like Mangler over an aggressive beater like Wolves
Up for debate. Anyway, this is a rough idea of what you could build. Seems better than RB.