Goopi

The Goopi is a small gelatinous creature that can stretch to eat or engulf Pikmin.

=In fanon games=

In Pikia
The Goopi is an enemy appearing immediately at the beginning of Pikia. They are of several different colors, remain in place, and stretch their neck out to eat Pikmin only of matching color, at a pace of roughly every ten seconds. It has very little vitality and takes roughly three seconds to kill. The most common color of Goopi is red.