This loop relies on an infinite recursive chain of creature replication and entering-the-battlefield triggers, starting when you use Cackling Counterpart to spin up your first copy of Restoration Angel. Once that Angel enters the battlefield, its blink trigger resets another creature with power 4 or greater, which in turn triggers Life Finds a Way to continuously populate fresh token copies of the Restoration Angel. Because each newly generated Angel immediately triggers another cycle of blinking and populating, the whole assembly becomes self-sustaining.