Boktai 2: Solar Boy Django

Boktai 2: Solar Boy Django (続・ボクらの太陽 太陽少年ジャンゴ, Zoku Bokura no Taiyō Taiyō Shōnen Jango, lit. Our Sun 2: Solar Boy Django), also known as Zoktai, is a video game that was developed and published by Konami for the Game Boy Advance. Released in North America and Japan in 2004 and in Europe in 2005, it is the sequel to Boktai: The Sun Is in Your Hand.
Boktai 2's game cartridge includes a photometric light sensor that measures the amount of sunlight/uv rays exposed to it.