Play Bokura no Taiyou : Taiyou Action RPG : Kabunushi Go-Yuut Online

Bokura no Taiyou: Taiyou Action RPG, known as Boktai in the west, was a 2003 Game Boy Advance release from Konami, with Hideo Kojima credited as producer. It arrived late in the GBA's life, a time when developers were still finding inventive ways to use the hardware beyond its obvious strengths.

You control Django, a young Solar Boy who ventures into monster-infested ruins to purify them with a solar weapon called the Gun Del Sol. Your main objective is to hunt vampires and other creatures of the night by gathering solar energy. The core mechanic involves a physical sunlight sensor built into the cartridge; you must play in actual sunlight or under a strong lamp to charge your weapons. This forces you to plan your play sessions around the weather and time of day, integrating the real world into the gameplay. Exploration happens screen by screen in top-down dungeons where you sneak past or confront enemies, using charged shots to incinerate them. The pacing is deliberate, with the energy management adding a layer of strategy to the combat. It feels like a puzzle you solve with sunlight and timing, not just reflexes.