Herd Baloth, Death's Presence, and Phyrexian Altar

Prerequisites

• Herd Baloth on the battlefield
• Death's Presence on the battlefield
• Phyrexian Altar on the battlefield
• You control at least one additional creature

Steps

1. Activate Phyrexian Altar by sacrificing any other creature, adding one mana of any color
2. Death's Presece triggers, putting a number of +1/+1 counters on Herd Baloth equal to the sacrificed creature's power
3. Herd Baloth triggers, creating a 4/4 Beast creature token
4. Repeat

Results

• Infinite +1/+1 counters on Herd Baloth
• Infinite colored mana
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite sacrifice triggers