From the Super Mario Wiki, the Mario encyclopedia
Mini Pi'illoids are support background enemies released by Pi'illodium in Mario & Luigi: Dream Team. They closely resemble Pi'illodium's head, except they always have red eyes. At the start of the battle with Pi'illodium, it releases four Mini Pi'illoids, the maximum there ever is on the battlefield at any one time. In battle, their role is to be used in one of Pi'illodium's attacks and to heal it and its wings when need be. It heals the wings by 45 HP per Mini Pi'illoid healing, but only when both wings have been disabled. They can be manually picked off one by one with the use of Taunt Balls.
Pi'illodium may use a Mini Pi'illoid in one of its attacks, spinning near it to smack it at Mario and Luigi, attempting to make it explode on the Bros.. If the Bros. send it back, it turns into a rally until either side fails to receive the Mini Pi'illoid and it explodes on or near the losing side. Regardless of the outcome, the Mini Pi'illoid used in this attack is subtracted from the Mini Pi'illoids currently in the background, and thus, this attack cannot be performed if there are no Mini Pi'illoids in the background.
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