Maindeck cuts:

1 death's shadow
2 phyrexina unlife
1 rite of consumption
1 messengers speed

Maindeck Ideas:

Moar red sources
Moar scrylands

1 Messenger's Speed / Crimson Wisps -> 1 Rite of Consumption
1 Phyretic Ritual (extra spirit guide)
? Mardu Charm
x Faithless Looting
x Plunge into Darkness
x Night's Whisper / Read the Bones
x Lotus Bloom

Sideboard:

1 Molten Slagheap
1 Duress
1 Wear // Tear
3 Pyroclasm
1 Spellskite
2 Phyrexian Arena
1 Timely Reinforcements
3 Leyline of Sanctity
2 Ranger of Eos

SB Ideas:
x Kataki, War's Wage / Stony Silence
x Rest in Peace
x Ignorant Bliss
x Rakdos Charm
x Orzhov Charm
x Wall of Omens
x Drown in Sorrow
x Lose Hope
1 Darkblast
1 Guttural Response
1 Silence
1 Patricians Scorn
x Aegis of the Gods/True Believer
1 Favor of the Mighty (twin/boggles/infect)
1 Boseiju, Who Shelters All