Koll, the Forgemaster + Sai of the Shinobi + Crimson Kobolds + Goblin Bombardment

Koll, the Forgemaster

Sai of the Shinobi

Crimson Kobolds

Goblin Bombardment

How it works

1. Cast Crimson Kobolds by paying 0.
2. When Crimson Kobolds enters the battlefield, Sai of the Shinobi triggers, attaching Sai of the Shinobi to Crimson Kobolds.
3. Activate Goblin Bombardment by sacrificing Crimson Kobolds.
4. When Crimson Kobolds dies, Koll triggers, returning Crimson Kobolds from your graveyard to your hand.
5. Resolve the Goblin Bombardment ability, dealing 1 damage to any target.
6. Repeat.

This clever loop turns zero-mana creatures into a lethal artillery battery by leveraging the synergy between Koll, the Forgemaster and Goblin Bombardment. Because Crimson Kobolds costs nothing to cast, it hits the battlefield for free and immediately triggers Sai of the Shinobi to suit it up with an Equipment, which also satisfies Koll's requirement for returning the creature to your hand upon death. Once Goblin Bombardment sacrifices the Kobold, Koll scoops it right back to your hand so you can recast it endlessly, converting free creature spells into an infinite stream of damage.