Gunma-chan, Uncle Akio, Aoma, and Meemi visit Gunma's kofun site and wander into an alternate world beneath Gunma in the Season 2 finale.
Who knew it was so big down here...
Ich wusste nicht,
dass es hier unten so groß ist.
C’est sacrément grand, ici-bas.
Chi se lo immaginava
che qui sotto fosse così ampio...
Nunca imaginei que fosse
tão grande aqui embaixo...
Какое огромное подземелье!