Upgraded Meren (EDH / Commander)

Card draw - 10

Skullclamp
Phyrexian Arena
Night's Whisper
Sign in Blood
Read the Bones
Grim Haruspex
Solemn Simulacrum
Nurturing Peatland
Oracle of Mul Daya
Disciple of Bolas

Ramp - 16

Sol Ring
Wild Growth
Awakening Zone
Farseek
Rampant Growth
Cultivate
Kodama's Reach
Arbor Elf
Birds of Paradise
Deathrite Shaman
Elves of Deep Shadow
Elvish Mystic
Fyndhorn Elves
Llanowar Elves
Oracle of Mul Daya
Solemn Simulacrum

Sac Outlets - 8

High Market
Phyrexian Tower
Altar of Dementia
Ashnod's Altar
Birthing Pod
Carrion Feeder
Viscera Seer
Razaketh, the Foulblooded

Removal - 17

Bojuka Bog
Nature's Claim
Tragic Slip
Abrupt Decay
Hero's Downfall
Krosan Grip
Putrefy
Torment of Hailfire
Toxic Deluge
Caustic Caterpillar
Deathrite Shaman
Fleshbag Marauder
Merciless Executioner
Plaguecrafter
Reclamation Sage
Archfiend of Depravity
Massacre Wurm

Life Drain - 9

Sanguine Bond
Exsanguinate
Torment of Hailfire
Deathrite Shaman
Blood Artist
Zulaport Cutthroat
Falkenrath Noble
Gray Merchant of Asphodel
Kokusho, the Evening Star

Life Gain - 10

High Market
Sanguine Bond
Exsanguinate
Deathrite Shaman
Blood Artist
Zulaport Cutthroat
Disciple of Bolas
Falkenrath Noble
Gray Merchant of Asphodel
Kokusho, the Evening Star

Tutor Cards - 8

Birthing Pod
Pattern of Rebirth
Demonic Tutor
Diabolic Intent
Buried Alive
Fauna Shaman
Fierce Empath
Razaketh, the Foulblooded

Recursion - 8

Yavimaya Hollow
Pattern of Rebirth
Thrilling Encore
Living Death
Apprentice Necromancer
Eternal Witness
Mikaeus, the Unhallowed
Meren of Clan Nel Toth

Win Combos

Cast Avenger of Zendikar to create tokens. Sacrifice it to Ashnod's Altar and get the triggered effect of Mikaeus, the Unhallowed to double your tokens or recur it at your end step with Meren of Clan Nel Toth then either on the same or next turn you can sacrifice the tokens for mana to cast either Torment of Hailfire or Exsanguinate to severally damage or finish off your opponents. Earliest this can happen would be turn with the maximum mana spent on the highest cards Turn 5 to start cycling this combo, but on avg you'll probably start this cycle on turn 7 or 8.

TLDR: Avenger of Zendikar + Ashnod's Altar + Mikaeus, the Unhallowed or Meren of Clan Nel Toth + Torment of Hailfire or Exsanguinate

You'll want Mikaeus, the Unhallowed or Meren of Clan Nel Toth on the battlefield already then cast Gray Merchant of Asphodel or Kokusho, the Evening Star and sacrifice them to Ashnod's Altar or Carrion Feeder or Viscera Seer to start recurring them for their effects.

TLDR: Gray Merchant of Asphodel or Kokusho, the Evening Star + Mikaeus, the Unhallowed or Meren of Clan Nel Toth + Ashnod's Altar or Carrion Feeder or Viscera Seer

Cast Avenger of Zendikar to create tokens. Then sacrifice it to Ashnod's Altar or Carrion Feeder or Viscera Seer to trigger Mikaeus, the Unhallowed to double your tokens or recur it at your end step with Meren of Clan Nel Toth once you have about or close to 12 tokens drop Craterhoof Behemoth and swing at everyone. This will do 36 damage to 3 other players which at this point should be lethal. This combo will be a turn 6 or 7 at the earliest if you don't miss a land drop.

Avenger of Zendikar + Ashnod's Altar or Carrion Feeder or Viscera Seer + Mikaeus, the Unhallowed or Meren of Clan Nel Toth + Craterhoof Behemoth

If you can't get one of the bigger combos rolling this will help you grind out the game.

Cast Avenger of Zendikar or Grave Titan or use the tokens generated from Awakening Zone then Sacrifice them to Ashnod's Altar or Carrion Feeder or Viscera Seer or Altar of Dementia to trigger Blood Artist or Zulaport Cutthroat or Falkenrath Noble

TLDR: Avenger of Zendikar or Grave Titan or Awakening Zone + Ashnod's Altar or Carrion Feeder or Viscera Seer + Blood Artist or Zulaport Cutthroat or Falkenrath Noble