Alesha, Who Smiles at Death + Crystalline Crawler + Aggravated Assault + Arcbound Overseer + Ashnod's Altar

Alesha, Who Smiles at Death

Crystalline Crawler

Aggravated Assault

Arcbound Overseer

Ashnod's Altar

How it works

1. Activate Crystalline Crawler's second ability by tapping it, putting a +1/+1 counter on it.
2. Activate Ashnod's Altar by sacrificing Arcbound Overseer, adding CC.
3. When Arcbound Overseer dies, it triggers, putting its +1/+1 counters on Crystalline Crawler.
4. Activate Crystalline Crawler's first ability three times by removing three +1/+1 counters from it, adding 1.
5. Activate Aggravated Assault by paying 3, causing you to untap all creatures you control and to get an additional combat and main phase after this one.
6. Declare Alesha as an attacker, triggering its ability, targeting Arcbound Overseer.
7. Activate Crystalline Crawler's first ability twice by removing two +1/+1 counters from it, adding W/BW/B.
8. Resolve the Alesha trigger, causing you to pay W/BW/B to return Arcbound Overseer from your graveyard to the battlefield tapped and attacking with six +1/+1 counters on it due to its modular ability.
9. Repeat.

This loop is a masterclass in recycling modular hardware through the graveyard, centering around Crystalline Crawler as both your mana battery and modular counter sponge. By sacrificing Arcbound Overseer to Ashnod's Altar, you cash it out for colorless mana while funneling its massive stack of counters back onto the Crawler, which readily strips them away for the exact colored mana needed to fuel Aggravated Assault. Meanwhile, Alesha, Who Smiles at Death leverages her attack trigger to continuously retrieve the fallen Arcbound Overseer from the graveyard, ensuring the loop never runs dry.