Reveillark + Activated Sleeper + Ashnod's Altar

Reveillark

Activated Sleeper

Ashnod's Altar

How it works

1. Activate Ashnod's Altar by sacrificing Reveillark, adding CC.
2. When Reveillark dies, it triggers, returning Activated Sleeper from your graveyard to the battlefield as a copy of Reveillark.
3. Activate Ashnod's Altar by sacrificing Activated Sleeper, adding CC.
4. When Activated Sleeper dies, it triggers, returning Activated Sleeper from your graveyard to the battlefield as a copy of Reveillark.
5. Repeat from step 3.

This elegant engine relies on a clever feedback loop centered around Reveillark and its ability to pull small threats back from the graveyard. By sacrificing Reveillark to Ashnod's Altar, you generate the raw mana needed to fuel the cycle while sending the bird straight to the graveyard to trigger its return effect. That trigger lets you pull out Activated Sleeper, which sneaks onto the battlefield as a fresh copy of Reveillark. Sacrificing that copy back to Ashnod's Altar triggers its own copy of the leave-the-battlefield ability, allowing the Activated Sleeper to continuously resurrect itself in an endless loop that generates infinite colorless mana along with infinite death and sacrifice triggers.