you probabl solved it by now but if you haven’t had already… the key stone / stone tablet is a clue for other treasure in far left of the mountain. where the big stone is, the tablet is a clue for picking up berries in a certain order. (it’s on YT too if you want to look it up yourself) 😊
I just have one treasure missing !! Please help me ! I have these : Nara-Period Currency Heian-Period Currency 1 Hean-Period Currency 2 Koban Stone Tool 1 Stone Tool 2 Stone Knife Silver Coin Gold Seal Bronze Weight Dogu Yayoi Earthenware Yaman arthenware Bronze Sword