Alesha, Who Smiles at Death + Crystalline Crawler + Aggravated Assault + Arcbound Overseer + Krark-Clan Grunt

Alesha, Who Smiles at Death

Crystalline Crawler

Aggravated Assault

Arcbound Overseer

Krark-Clan Grunt

How it works

1. Activate Crystalline Crawler's second ability by tapping it, putting a +1/+1 counter on it.
2. Activate Krark-Clan Grunt by sacrificing Arcbound Overseer.
3. When Arcbound Overseer dies, it triggers, putting its +1/+1 counters on Crystalline Crawler.
4. Resolve the Krark-Clan Grunt ability.
5. Activate Crystalline Crawler's first ability five times by removing five +1/+1 counters from it, adding 3.
6. 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.
7. Declare Alesha as an attacker, triggering its ability, targeting Arcbound Overseer.
8. Activate Crystalline Crawler's first ability twice by removing two +1/+1 counters from it, adding W/BW/B.
9. 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.
10. Repeat.

This loop relies on Crystalline Crawler acting as our central mana engine, converting counters into the exact colors needed to fuel Aggravated Assault's extra combat phases. To keep the cycle going, Krark-Clan Grunt serves as a convenient sacrifice outlet to bin Arcbound Overseer, whose modular ability shifts its six counters right back onto Crystalline Crawler. Meanwhile, Alesha, Who Smiles at Death brings Arcbound Overseer straight back to the battlefield tapped and attacking during the extra combats, ensuring our entire engine resets seamlessly.