Kaminari Kogoro

Kaminari Kogoro (カミナリ小五郎) is an outdoor surveillance mecha from the Mega Man series that first appeared in Mega Man 7. On sunny days Kaminari Kogoro uses solar cells to accumulate electricity, using it to discharge thunders on rainy days.

Mega Man 7
Kaminari Kogoro is an enemy that appears in Cloud Man's stage and Wily Stage 1. Like Up'n'Down, Kaminari Kogoros emerge from pits when appeoached, and slowly returns to it. However, in a rainy or snowy weather it will also shoot thunder bolts downwards to shock Mega Man before returning to the pit. In Wily Stage 1, some will simply fall back while others will release a thunder.

Mega Man 2: The Power Fighters
Kaminari Kogoros appear during the battle with Elec Man in the "Rescue Roll!" course.

Mega Man: Battle & Chase
Kaminari Kogoro (written as カミナリコゴロー in the Japanese version) appears as an item. When used, a Kaminari Kogorō appears above opponents and shocks them, slowing them down for a short time.

Other media
Kaminari Kogoros appeared briefly in the Rockman 7 manga, one of them warning Cloud Man of Mega Man's progress.

Etymology
Like Kaminari Goro, Kaminari means "thunder" in Japanese, and Gorō is a common Japanese male given name. The "ko" in Kogoro means "small", suggesting that it may be a miniaturized version of Kaminari Goro.