This loop relies on Isilu, Carrier of Twilight's passive grant of persist to give Cultivator of Blades a way to cheat death over and over again. When you sacrifice Cultivator of Blades to Goblin Bombardment, it returns with a -1/-1 counter, but its own fabricate ability immediately places a +1/+1 counter on it, which neatly cancels out the penalty via state-based actions. Because the counter is removed, the cycle can repeat indefinitely, letting Goblin Bombardment fling infinite damage at any target. While Eirdu, Carrier of Dawn sits on the reverse side waiting for its moment to flip, it's Isilu's static resilience combined with Fabricate that lets you turn a single creature into an endless engine of destruction.