Game de Hakken!! Tamagotchi: Osutchi to Mesutchi builds on Bandai's virtual-pet series by letting players raise a male (Osutchi) and a female (Mesutchi) and pair them, a Japan-only release that is Super Game Boy enhanced.
Its cartridge is one of the most unusual ever made for the Game Boy: a custom Toshiba TAMA5 board with a dedicated co-processor and a battery-backed real-time clock, so the Tamagotchi keeps living and ageing in real time even when the console is switched off. No other Game Boy game used this TAMA5 hardware. The oversized cartridge also carries its own small built-in speaker, controlled by a physical sound on/off switch on the shell, so the pet can chirp and sound its alerts directly from the module.
More from the Museum's Journal: The Tamagotchi Cartridges: Three Pet Sims, and One of the Rarest Boards in Game Boy History.
