Leonardo, Sewer Samurai + Solemnity + Ashnod's Altar + Kobolds of Kher Keep

Leonardo, Sewer Samurai

Solemnity

Ashnod's Altar

Kobolds of Kher Keep

How it works

1. Activate Ashnod's Altar by sacrificing Kobolds of Kher Keep.
2. Cast Kobolds of Kher Keep from your graveyard by paying 0. It will not enter with a finality counter on it due to Solemnity.
3. Repeat.

This ingenious loop turns the humble Kobolds of Kher Keep into an engine for infinite mana and sacrifice triggers, completely bypassing the drawback of Leonardo, Sewer Samurai. While Leonardo normally exiles creatures cast from your graveyard by giving them finality counters, Solemnity’s passive ability steps in to prevent those counters from ever being placed. This allows you to endlessly sacrifice the Kobolds to Ashnod's Altar for colorless mana and recast them for zero mana right back from the graveyard.