It's been a whopping 21 years since Boktai: The Sun is in Your Hand launched in Japan on 17th July 2003, and one person commemorating the anniversary is none other than producer and designer Hideo Kojima.
Posting on social media, the auteur recalled that it was "raining hard" on the game's release day. This might be an odd thing to remember, you might think, but those who have played Boktai will know that its gameplay is heavily dependent on the cartridge's light sensor, requiring you to often play in direct sunlight.
Naturally, then, we can't imagine many folks in Japan would have managed to go outdoors on Boktai's release day.
Still, the game was reasonably well received and went on to spawn three sequels: Boktai 2: Solar Boy Django, Boktai 3: Sabata's Counterattack, both on the GBA, and Lunar Knights for the Nintendo DS. The latter removed mandatory use of sunlight, but you could still make use of this if you inserted one of the first two cartridges into the DS's GBA slot.