The Illerpillar is a recurring monster in the Dragon Quest series, first appearing in Dragon Quest III. It is a caterpillar monster that poisons parties of adventurers with its toxic breath.
Illerpillars are enormous caterpillars with vivid teal bodies and either purple or light grey undersides with a set of six orange limbs. They have tiny faces and a set of blue or purple spots on the side of its head that look like eyes. The caterpillars attack by rolling themselves up and striking at enemies with the sharp stinger at the end of their tails. They are known for their characteristic ability to poison novice adventurers with their breath.