Ghave, Guru of Spores, Phyrexian Altar, Butcher Ghoul, and Corpse Knight

Prerequisites

• Ghave, Guru of Spores on the battlefield
• Phyrexian Altar on the battlefield
• Butcher Ghoul on the battlefield
• Corpse Knight on the battlefield
• Butcher Ghoul does not have a +1/+1 counter on it

Steps

1. Activate Phyrexian Altar by sacrificing Butcher Ghoul, adding
2. Butcher Ghoul's undying triggers, returning Butcher Ghoul from your graveyard to the battlefield with a +1/+1 counter on it
3. Butcher Ghoul 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 Butcher Ghoul, 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 colored mana
• Infinite creature tokens
• Infinite ETB
• Infinite lifeloss
• Infinite LTB
• Infinite +1/+1 counters
• Infinite sacrifice triggers
• Infinite death triggers