Toph, Greatest Earthbender + Power Depot + Crystalline Crawler + Goblin Bombardment + Brad Boimler, Eager Ensign

Toph, Greatest Earthbender

Power Depot

Crystalline Crawler

Goblin Bombardment

Brad Boimler, Eager Ensign

How it works

1. Play Power Depot, which will enter with a +1/+1 counter on it due to its modular ability
2. Cast Toph either from your hand or from the command zone by paying 2 plus commander tax if applicable.
3. When Toph enters, it triggers, earthbending Power Depot and putting a number of +1/+1 counters on Power Depot equal to the mana spent to cast Toph, increased by Brad Boimler.
4. Activate Goblin Bombardment by sacrificing Power Depot.
5. When Power Depot dies, its modular ability and Toph trigger.
6. Resolve the modular trigger, putting the +1/+1 counters that were on Power Depot onto Crystalline Crawler, increased by Brad Boimler.
7. Resolve the Toph trigger, returning Power Depot from your graveyard to the battlefield tapped. Power Depot will enter with a +1/+1 counter on it due to its modular ability
8. Resolve the Goblin Bombardment ability.
9. Activate Goblin Bombardment by sacrificing Toph. Choose to return Toph from your graveyard to the command zone.
10. Activate Crystalline Crawler by removing a +1/+1 counter from it, adding R/G.
11. Repeat step 10 until you have enough mana to cast Toph.
12. Repeat from step 2.

This loop uses Toph, Greatest Earthbender to repeatedly animate and sacrifice Power Depot, turning a simple land into a bottomless well of counters and triggers. Because Brad Boimler, Eager Ensign increases the number of counters being placed on your permanents whenever he taps, Crystalline Crawler rapidly accumulates a massive surplus of +1/+1 counters that can be peeled off for mana. That generated mana pays to recast Toph and fuel the cycle anew, letting Goblin Bombardment fling endless sacrifices at your opponents until they crumble to dust.