Greenman vs. Giringa (グリーンマン対ギリンガ, Gurīnman tai Giringa?) is the twenty-ninth episode of Go! Greenman.
Gathered around a mountain-like model, Maoh and Tonchiki briefly talk before a nearby minion is transformed into the monster Giringa. Demonstrating his punching ability, Giringa knocks the model off of its pedestal and straight into Maoh's face. Tonchiki apologizes for Giringa's misbehavior and teleports to a bush with the monster. There, a boy breaks from a group and wanders past the bush only to be pursued by Giringa. The monster tries to grab hold of the child but only ends up knocking into Tonchiki. The boy runs a distance away before activating his Green Call. Following the device's signal, Greenman appears on the scene and battles Giringa. However, Greenman easily counters all of Giringa's attacks, sending the monster running. Disappointed and fearing Greenman's victory, Tonchiki orders Giringa to grow. Greenman is not fazed by the sudden size difference, and utilizing the vast technology found within himself, grows to giant size as well. Their battle continues in a mountainous town. After much hand-to-hand combat, Greenman backs away to fire a Leg Arrow, but Giringa evades the projectile. Albeit, Greenman tries again, this time the arrow becoming lodged in Giringa's right hand. Greatly pained by the arrow, Giringa retaliates with a series of full-force punches which leave Greenman motionless on the ground. Realizing their hero's defeat, a boy close by uses a Green Call and "revives" Greenman. They engage once again in a final battle, in the middle of which Greenman throws an Ear Boomerang at Giringa which he dodges. Similarly to before, Greenman throws a second Ear Boomerang, this time making contact with the monster's fist. Giringa attempts to escape by running up a mountain but is stopped when Greenman fires a Mouth Beam, killing the cowardly kaiju.