A number of enemies in the Pikmin series can revive after death if tbeir body is left alone. It is known that Spotty Bulbears and Gatling groinks have this ability. When you kill an enemy that can revive, its HP will slowly regenerate until it simply gets up and continues attacking. To avoid this happening, defeat the enemy while it is petrified so that its body disappears, make it fall down a hole (applicable in certain caves), return the body to the Research Pod or The Ship, or quickly progress to the next sublevel if underground.If there are enemys between the enemy that's reviving and the rocket/onion, get rid of them, quick. if you don't have time to kill them, feel free to panic, go cross eyed, blither, and genrally make a fool of yourself. You will not be ridiculed, as chances are you'll have to fight the accursed thing all over again.
Please feel free to blither now.