Kābī no Omochabako (partially lost Satellaview minigames; 1996)
Kirby's Toy Box is the translated name of a small series of Kirby sub-games titled カービィのおもちゃ箱 (Kābī no Omochabako, meaning Kirby's Toy Box) in Japan. The Kirby's Toy Box series was broadcast over Nintendo's first form of digital distribution, the Satellaview satellite network, and, depending on when the player connected to the network, different games were available at different times. These could be downloaded to the Satellaview base unit, or an 8-megabit rewritable "Memory Pak" ROM cartridge compatible with the Satellaview
Because of the Discontinuation of the Satellaview in 1997, the 9 minigames, and the rest of the satellaview games, fell into obscurity with no re-releases since and making them completely lost.
In November of 2016, A group of Gaming preservationists, got a hold of a few off these of the Kirby Toybox minigames, and dumped them online for the public to see. And on the 6th of the same month, another group found four of the other games at an auction in japan. they were also successfully dumped online for the public and can now be played through emulation
Only one minigames is lost and that's Ball Rally, but for now only 8 of the 9 minigames have been found
References: https://satellaview.org/ : Where the Kirby Toybox minigames can be downloaded