This clever loop hinges on the unique rules of mutation, transforming Kiki-Jiki, Mirror Breaker and Parcelbeast into a single unified entity that possesses both the iconic ability-copying power of the goblin shaman and the utility of the beast. Because the combined creature retains Kiki-Jiki's activated ability, tapping the merged creature lets you create a token copy that *also* enters the battlefield with all of Parcelbeast's stacked abilities intact. You can repeat this process as many times as you desire, flooding the board with an endless army of hasty, tapped creature tokens while generating an infinite stream of enters-the-battlefield, leaves-the-battlefield, and death triggers.