Ghave, Guru of Spores, Ashnod's Altar, Strangleroot Geist, and Corpse Knight

Prerequisites

• Ghave, Guru of Spores on the battlefield
• Ashnod's Altar on the battlefield
• Strangleroot Geist on the battlefield
• Corpse Knight on the battlefield
• Strangleroot Geist does not have a +1/+1 counter on it

Steps

1. Activate Ashnod's Altar by sacrificing Strangleroot Geist, adding
2. Strangleroot Geist's undying triggers, returning Strangleroot Geist from your graveyard to the battlefield with a +1/+1 counter on it
3. Strangleroot Geist enters the battlefield triggering Corpse Knight, causing each opponent to lose 1 life
4. Activate Ghave's second ability by paying and removing a +1/+1 counter from Strangleroot Geist, creating a 1/1 Saproling creature token
5. The Saproling token enters the battlefield triggering Corpse Knight, causing each opponent to lose 1 life
6. Repeat

Results

• Infinite colorless mana
• Infinite creature tokens
• Infinite ETB
• Infinite lifeloss
• Infinite LTB
• Infinite +1/+1 counters
• Infinite sacrifice triggers
• Infinite death triggers