Harobots is a game series developed by Sunrise Interactive, it features Haro from Gundam series, as a protagonist's pet. Haro can be customized and battle for its trainer from any mecha series by Sunrise. This game series never released outside Japan due to series' license for US.
Released games in the series are
- Harobots for Game Boy
- Harobots for WonderSwan
- GB Harobots for Game Boy Color
- Harobots: Robo Hero Battling! for Game Boy Advance
- Harobots Action for Nintendo DS
Source: Wikipedia, "Harobots", available under the CC-BY-SA License.