The Story of Thor: A Successor of the Light/Bugs
From Sega Retro
Out of bounds
Due to the way the game's maps are coded, it is possible to go out of bounds in the forest area, allowing the player to get access to the mountain area early, however they won't be able to progress further in the game unless they've unlocked Dytto and Efreet before doing this.
Not fixed in any version.
References