Keroro, The world's Sgt. Keroros / Keroro, Keron Army Style Excursion Great Opening!
Sergeant Keroro tries to invade the world by making multiple copies of himself, and then the platoon tries to do military training exercises because they think Fuyuki is doing them. Source: crunchyroll
Aired 04/04/2011EP 358 - Keroro, The world's Sgt. Keroros / Keroro, Keron Army Style Excursion Great Opening!
2004
Sgt. Frog
Keroro is a frog-like alien sent from his home planet on a mission to conquer Earth. But when his cover is blown, his battalion abandons him and he ends up in the home of the Hinata family. There, he's forced to do household chores and sleep in a dark basement that was once supposedly a prison cell haunted by the ghost of an innocent girl. He even spends his free time assembling Gundam model kits. During his stay, Keroro meets up with subordinates who were also stranded during their failed invasion.
(Source: Anime News Network)