Szarel, Genesis Shepherd, Crystalline Crawler, Slimefoot and Squee, and Ashnod's Altar

Prerequisites

• Szarel, Genesis Shepherd on the battlefield
• Crystalline Crawler on the battlefield
• Slimefoot and Squee in the graveyard
• Ashnod's Altar on the battlefield
• available

Steps

1. Activate Slimefoot and Squee by paying and sacrificing a Saproling, returning it and up to one other creature card from your graveyard to the battlefield
2. When Slimefoot and Squee enters the battlefield, it triggers, creating a 1/1 Saproling creature token
3. Activate Ashnod's Altar by sacrificing Slimefoot and Squee, and the other creature returned in step 1, if applicable, adding for each creature sacrificed
4. When Slimefoot and Squee and up to one other creature are sacrificed, Szarel triggers that many times, putting a number of +1/+1 counters equal to Szarel's power on Crystalline Crawler for each trigger
5. Activate Crystalline Crawler three times by removing three +1/+1 counters from it, adding
6. Repeat

Results

• Infinite LTB
• Infinite ETB
• Infinite colored mana
• Infinite sacrifice triggers
• Infinite death triggers
• Infinite colorless mana
• Infinite +1/+1 counters
• Infinite recursion of creature cards in your graveyard