Prowling Geistcatcher, Kiki-Jiki, Mirror Breaker, and Ashnod's Altar

Prerequisites

• Prowling Geistcatcher on the battlefield
• Kiki-Jiki, Mirror Breaker on the battlefield
• Ashnod's Altar on the battlefield

Steps

1. Activate Kiki-Jiki by tapping it, creating a token copy of Prowling Geistcatcher with haste
2. Activate Ashnod's Altar by sacrificing Kiki-Jiki, adding
3. When Kiki-Jiki dies, the nontoken and token Prowling Geistcatcher's first abilities trigger
4. Resolve the token Prowling Geistcatcher's trigger, exiling Kiki-Jiki from your graveyard
5. Resolve the nontoken Prowling Geistcatcher's trigger, doing nothing
6. Activate Ashnod'sAltar by sacrificing the Prowling Geistcatcher token, adding
7. When the token Prowling Geistcatcher dies, its second ability and the nontoken Prowling Geistcatcher's first ability triggers
8. Resolve the nontoken Prowling Geistcatcher trigger, putting a +1/+1 counter on it
9. Resolve the token Prowling Geistcatcher trigger, returning Kiki-Jiki from exile to the battlefield
10. Repeat

Results

• Infinite +1/+1 counters on Prowling Geistcatcher
• Infinite colorless mana
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite sacrifice triggers