Activate Ashnod's Altar by sacrificing Diregraf Horde, adding {C}{C}.
Diregraf Horde dies, triggering Nim Deathmantle, causing you to pay {4} to return Diregraf Horde from your graveyard to the battlefield, and attach Nim Deathmantle to it.
Diregraf Horde enters the battlefield, creating two 2/2 Zombie creature tokens.
Activate Ashnod's Altar by sacrificing a Zombie, adding {C}{C}.
Repeat.

Infinite colorless mana

Infinite creature tokens

Infinite death triggers

Infinite creature ETB

Infinite creature LTB

Infinite creature sacrifice triggers

Nim Deathmantle

Ashnod's Altar

Diregraf Horde

Activate Eldrazi Displacer by paying {2}{C}, blinking Diregraf Horde.
When Diregraf Horde enters, it triggers, creating two creature tokens.
Activate Ashnod's Altar by sacrificing two creature tokens, adding {C}{C}{C}{C}.
Repeat.

Infinite blinking

Infinite blinking of most creatures

Eldrazi Displacer

Activate Diregraf Horde by paying {1}{U}, blinking it.
When Diregraf Horde enters the battlefield, it and Deadeye Navigator's soulbond ability triggers.
Resolve the Deadeye Navigator trigger, repairing it and Diregraf Horde.
Resolve the Diregraf Horde trigger, creating two 2/2 Zombie creature tokens.
Activate Phyrexian Altar twice by sacrificing the Zombies, adding {1}{U}.
Repeat.

Deadeye Navigator

Phyrexian Altar

Activate Diregraf Horde by paying {1}{U}, blinking it.
When Diregraf Horde enters the battlefield, it and Deadeye Navigator's soulbond ability triggers.
Resolve the Deadeye Navigator trigger, repairing it and Diregraf Horde.
Resolve the Diregraf Horde trigger, creating two 2/2 Zombie creature tokens.
Activate Ashnod's Altar twice by sacrificing the Zombies, adding {C}{C}{C}{C}.
Activate Urn of Godfire by paying {2}, adding {U}.
Repeat.

Infinite colored mana

Urn of Godfire

Activate Diregraf Horde by paying {2}, blinking it.
When Diregraf Horde enters the battlefield, it and Deadeye Navigator's soulbond ability triggers.
Resolve the Deadeye Navigator trigger, repairing it and Diregraf Horde.
Resolve the Diregraf Horde trigger, creating two 2/2 Zombie creature tokens.
Activate Ashnod's Altar by sacrificing a Zombie, adding {C}{C}.
Repeat.

Infinite card draw

Infinite draw triggers

Chromatic Orrery

Mycosynth Lattice

Activate Emiel by paying {3}, blinking Diregraf Horde.
Diregraf Horde enters the battlefield, creating two 2/2 Zombie creature tokens.
Activate Ashnod's Altar by sacrificing the Zombie tokens, adding {C}{C}{C}{C}.
Repeat.

Combos with "Diregraf Horde"