Keroro Gunsou Movie 5: Tanjou! Kyuukyoku Keroro, Kiseki no Jikuu-jima, de Arimasu!!
English name: Keroro Gunso the Super Movie: Creation! Ultimate Keroro, Wonder Space-Time Island!!
Genres: Comedy
Type: Movie, Episodes: 1
Aired: Feb 27, 2010
Studio: Sunrise
Source: Manga
Rating: PG - Children
Synopsis:
One day, a stone carving bearing an uncanny likeness to Keroro  arrives at Fuyumi's place. To solve this mystery, the Keroro Squad travels to the isolated and mysterious Easter Island. There, they meet harmless spirits known as Mana, and the odd twins Io and Rana. Lastly, there is Akuaku, a legendary evil spirit recently awoken from its long sleep. 

(Source: AniDB)